MASSMUTUAL INSTITUTIONAL FUNDS
NSAR-B, 1998-02-24
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<PAGE>      PAGE  1
000 B000000 12/31/97
000 C000000 0000916053
000 D000000 N
000 E000000 NF
000 F000000 Y
000 G000000 N
000 H000000 N
000 I000000 3.0.a
000 J000000 U
001 A000000 MASSMUTUAL INSTITUTIONAL FUNDS
001 B000000 811-8274
001 C000000 4137888411
002 A000000 1295 STATE STREET
002 B000000 SPRINGFIELD
002 C000000 MA
002 D010000 01111
002 D020000 0001
003  000000 N
004  000000 N
005  000000 N
006  000000 N
007 A000000 Y
007 B000000  7
007 C010100  1
007 C020100 MASSMUTUAL PRIME FUND
007 C030100 N
007 C010200  2
007 C020200 MASSMUTUAL SHORT-TERM BOND FUND
007 C030200 N
007 C010300  3
007 C020300 MASSMUTUAL CORE BOND FUND
007 C030300 N
007 C010400  4
007 C020400 MASSMUTUAL BALANCED FUND
007 C030400 N
007 C010500  5
007 C020500 MASSMUTUAL VALUE EQUITY FUND
007 C030500 N
007 C010600  6
007 C020600 MASSMUTUAL SMALL CAP VALUE EQUITY FUND
007 C030600 N
007 C010700  7
007 C020700 MASSMUTUAL INTERNATIONAL EQUITY FUND
007 C030700 N
007 C010800  8
007 C010900  9
007 C011000 10
010 A00AA01 MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY
010 B00AA01 801-8059
010 C01AA01 SPRINGFIELD`
010 C02AA01 MA
<PAGE>      PAGE  2
010 C03AA01 01111
010 C04AA01 0001
010 A00AA02 INVESTORS BANK & TRUST COMPANY(SUBADM)
010 B00AA02 85-720
010 C01AA02 BOSTON
010 C02AA02 MA
010 C03AA02 02116
011 A00AA01 OPPENHEIMERFUNDS DISTRIBUTOR, INC
011 B00AA01 8-22992
011 C01AA01 NEW YORK
011 C02AA01 NY
011 C03AA01 10048
011 A00AA02 MML INVESTORS SERVICES, INC.
011 B00AA02 8-27250
011 C01AA02 SPRINGFIELD
011 C02AA02 MA
011 C03AA02 01111
012 A00AA01 INVESTORS BANK & TRUST COMPANY
012 B00AA01 85-720
012 C01AA01 BOSTON
012 C02AA01 MA
012 C03AA01 02116
013 A00AA01 COOPERS & LYBRAND LLP
013 B01AA01 SPRINGFIELD
013 B02AA01 MA
013 B03AA01 01101
013 B04AA01 0059
014 A00AA01 MML INVESTORS SERVICES, INC.
014 B00AA01 8-27250
014 A00AA02 OPPENHEIMERFUNDS DISTRIBUTOR, INC
014 B00AA02 8-22992
014 A00AA03 CENTENNIAL ASSET MANAGEMENT CORPORATION
014 B00AA03 8-22948
014 A00AA04 MULTI SOURCE SERVICES, INC.
014 B00AA04 8-40450
014 A00AA05 BABSON SECURITIES, INC.
014 B00AA05 8-47589
018  00AA00 Y
019 A00AA00 Y
019 B00AA00   32
019 C00AA00 MASSMUTUAL
020 A000001 BEAR STEARNS & CO.INC.
020 B000001 13-3299429
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020 A000002 CREDIT SUISSE-FIRST BOSTON
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020 A000003 SCHRODER WERTHEIM & CO.INCORPORATED
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020 A000004 PERSHING DIVISION OF DLJ
<PAGE>      PAGE  3
020 B000004 13-2741729
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020 A000005 B.Z.W. SECURITIES INC.
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020 A000006 GOLDMAN SACHS & CO.
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020 A000007 SOCIETE GENERALE SECURITIES CORPORATION
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020 C000007    108
020 A000008 PAINE WEBER, INC.
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020 C000008    106
020 A000009 PRUDENTIAL SECURITIES INC.
020 B000009 22-2347336
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020 A000010 PARIBAS SECURTIES
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022 A000001 GOLDMAN SACHS & CO.
022 B000001 13-5108880
022 C000001   2335005
022 D000001    212075
022 A000002 MERRILL LYNCH, PIERCE, FENNER & SMITH, INC.
022 B000002 13-5674085
022 C000002   1878471
022 D000002    159917
022 A000003 MORGAN (J.P.) SECURITIES, INC.
022 B000003 13-3224016
022 C000003   1248430
022 D000003     92319
022 A000004 CREDIT SUISSE-FIRST BOSTON
022 B000004 13-5659485
022 C000004   1259095
022 D000004     51298
022 A000005 LEHMAN BROTHERS INC.
022 B000005 13-2518466
022 C000005   1221911
022 D000005     85397
022 A000006 MORGAN STANLEY & CO., INC.
022 B000006 13-2655998
022 C000006    906618
022 D000006     38560
022 A000007 BA INVESTMENT SERVICES, INC.
022 B000007 95-3783486
022 C000007    376821
022 D000007     18747
022 A000008 FIRST CHICAGO CAPITAL MARKETS
022 B000008 36-3595942
<PAGE>      PAGE  4
022 C000008    112905
022 D000008      2430
022 A000009 PRUDENTIAL SECURITIES INC.
022 B000009 22-2347336
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022 A000010 UBS SECURITIES LLC
022 B000010 13-3873456
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<PAGE>      PAGE  5
054 B00AA00 N
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<PAGE>      PAGE  6
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<PAGE>      PAGE  7
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<PAGE>      PAGE  8
070 A020100 N
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<PAGE>      PAGE  9
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<PAGE>      PAGE  10
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008 A000201 MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY
008 B000201 A
008 C000201 801-8059
008 D010201 SPRINGFIELD
008 D020201 MA
008 D030201 01111
008 D040201 0001
015 A000201 INVESTORS BANK & TRUST COMPANY
015 B000201 C
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015 C020201 MA
015 C030201 02116
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<PAGE>      PAGE  11
046  000200 N
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064 A000200 N
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<PAGE>      PAGE  12
066 A000200 N
067  000200 N
068 A000200 N
068 B000200 N
069  000200 N
070 A010200 Y
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070 C010200 Y
070 C020200 N
070 D010200 Y
070 D020200 N
070 E010200 Y
070 E020200 N
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070 G010200 Y
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070 H010200 Y
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070 J010200 Y
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<PAGE>      PAGE  13
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<PAGE>      PAGE  14
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008 A000301 MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY
008 B000301 A
008 C000301 801-8059
008 D010301 SPRINGFIELD
008 D020301 MA
008 D030301 01111
008 D040301 0001
015 A000301 INVESTORS BANK & TRUST COMPANY
015 B000301 C
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015 C020301 MA
015 C030301 02116
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<PAGE>      PAGE  15
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<PAGE>      PAGE  16
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<PAGE>      PAGE  17
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<PAGE>      PAGE  18
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008 A000401 MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY
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<PAGE>      PAGE  19
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<PAGE>      PAGE  23
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<PAGE>      PAGE  25
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008 A000701 MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY
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008 C000701 801-8059
008 D010701 SPRINGFIELD
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008 D030701 01111
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008 A000702 HARBOURVIEW ASSET MANAGEMENT CORPORATION
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<PAGE>      PAGE  32
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<PAGE>      PAGE  33
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<PAGE>      PAGE  35
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074 P000700      455
074 Q000700        0
074 R010700        0
074 R020700        0
074 R030700        0
074 R040700    24548
074 S000700        0
074 T000700   547182
074 U010700    44180
074 U020700       32
074 V010700     0.00
074 V020700     0.00
074 W000700   0.0000
074 X000700        4
<PAGE>      PAGE  37
074 Y000700        0
075 A000700        0
075 B000700   488181
076  000700     0.00
SIGNATURE   STEPHEN KUHN                                 
TITLE       VICE PRESIDENT      
 



<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 31
   <NAME> Core Bond Fund, Class 1
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      432,689,491
<INVESTMENTS-AT-VALUE>                     449,079,535
<RECEIVABLES>                               10,091,545
<ASSETS-OTHER>                                  46,527
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             459,217,607
<PAYABLE-FOR-SECURITIES>                         9,945
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    2,877,503
<TOTAL-LIABILITIES>                          2,887,448
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   438,706,742
<SHARES-COMMON-STOCK>                           12,073
<SHARES-COMMON-PRIOR>                           11,512
<ACCUMULATED-NII-CURRENT>                    1,094,301
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                         69,810
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                    16,459,306
<NET-ASSETS>                                   131,171
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                                8,580
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   2,083
<NET-INVESTMENT-INCOME>                          6,497
<REALIZED-GAINS-CURRENT>                           604
<APPREC-INCREASE-CURRENT>                        3,231
<NET-CHANGE-FROM-OPS>                           10,332
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        5,999
<DISTRIBUTIONS-OF-GAINS>                            55
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                561
<NET-CHANGE-IN-ASSETS>                          10,333
<ACCUMULATED-NII-PRIOR>                      1,845,746
<ACCUMULATED-GAINS-PRIOR>                   (1,885,881)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        1,869,877
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              2,292,770
<AVERAGE-NET-ASSETS>                           124,493
<PER-SHARE-NAV-BEGIN>                            10.50
<PER-SHARE-NII>                                   0.56
<PER-SHARE-GAIN-APPREC>                           0.33
<PER-SHARE-DIVIDEND>                             (0.51)
<PER-SHARE-DISTRIBUTIONS>                        (0.02)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              10.86
<EXPENSE-RATIO>                                   1.67
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 32
   <NAME> Core Bond Fund, Class 2
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      432,689,491
<INVESTMENTS-AT-VALUE>                     449,079,535
<RECEIVABLES>                               10,091,545
<ASSETS-OTHER>                                  46,527
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             459,217,607
<PAYABLE-FOR-SECURITIES>                         9,945
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    2,877,503
<TOTAL-LIABILITIES>                          2,887,448
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   438,706,742
<SHARES-COMMON-STOCK>                           12,265
<SHARES-COMMON-PRIOR>                           11,631
<ACCUMULATED-NII-CURRENT>                    1,094,301
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                         69,810
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                    16,459,306
<NET-ASSETS>                                   133,481
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                                8,707
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,420
<NET-INVESTMENT-INCOME>                          7,287
<REALIZED-GAINS-CURRENT>                           615
<APPREC-INCREASE-CURRENT>                        3,286
<NET-CHANGE-FROM-OPS>                           11,188
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        6,818
<DISTRIBUTIONS-OF-GAINS>                            55
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                634
<NET-CHANGE-IN-ASSETS>                          11,188
<ACCUMULATED-NII-PRIOR>                      1,845,746
<ACCUMULATED-GAINS-PRIOR>                   (1,885,881)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        1,869,877
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              2,292,770
<AVERAGE-NET-ASSETS>                           126,340
<PER-SHARE-NAV-BEGIN>                            10.51
<PER-SHARE-NII>                                   0.63
<PER-SHARE-GAIN-APPREC>                           0.33
<PER-SHARE-DIVIDEND>                             (0.57)
<PER-SHARE-DISTRIBUTIONS>                        (0.02)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              10.88
<EXPENSE-RATIO>                                   1.12
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 33
   <NAME> Core Bond Fund, Class 3
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      432,689,491
<INVESTMENTS-AT-VALUE>                     449,079,535
<RECEIVABLES>                               10,091,545
<ASSETS-OTHER>                                  46,527
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             459,217,607
<PAYABLE-FOR-SECURITIES>                         9,945
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    2,877,503
<TOTAL-LIABILITIES>                          2,887,448
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   438,706,742
<SHARES-COMMON-STOCK>                           12,379
<SHARES-COMMON-PRIOR>                           11,699
<ACCUMULATED-NII-CURRENT>                    1,094,301
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                         69,810
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                    16,459,306
<NET-ASSETS>                                   134,838
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                                8,781
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                     989
<NET-INVESTMENT-INCOME>                          7,792
<REALIZED-GAINS-CURRENT>                           621
<APPREC-INCREASE-CURRENT>                        3,318
<NET-CHANGE-FROM-OPS>                           11,731
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        7,342
<DISTRIBUTIONS-OF-GAINS>                            56
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                680
<NET-CHANGE-IN-ASSETS>                          11,731
<ACCUMULATED-NII-PRIOR>                      1,845,746
<ACCUMULATED-GAINS-PRIOR>                   (1,885,881)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        1,869,877
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              2,292,770
<AVERAGE-NET-ASSETS>                           127,404
<PER-SHARE-NAV-BEGIN>                            10.52
<PER-SHARE-NII>                                   0.67
<PER-SHARE-GAIN-APPREC>                           0.33
<PER-SHARE-DIVIDEND>                             (0.61)
<PER-SHARE-DISTRIBUTIONS>                        (0.02)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              10.89
<EXPENSE-RATIO>                                   0.78
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 34
   <NAME> Core Bond Fund, Class S
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      432,689,491
<INVESTMENTS-AT-VALUE>                     449,079,535
<RECEIVABLES>                               10,091,545
<ASSETS-OTHER>                                  46,527
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             459,217,607
<PAYABLE-FOR-SECURITIES>                         9,945
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    2,877,503
<TOTAL-LIABILITIES>                          2,887,448
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   438,706,742
<SHARES-COMMON-STOCK>                       42,182,957
<SHARES-COMMON-PRIOR>                       34,141,922
<ACCUMULATED-NII-CURRENT>                    1,094,301
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                         69,810
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                    16,459,306
<NET-ASSETS>                               455,930,669
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                           28,573,800
<OTHER-INCOME>                                       0
<EXPENSES-NET>                               2,238,917
<NET-INVESTMENT-INCOME>                     26,334,883
<REALIZED-GAINS-CURRENT>                     2,196,108
<APPREC-INCREASE-CURRENT>                   11,741,148
<NET-CHANGE-FROM-OPS>                       40,272,139
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                   27,133,147
<DISTRIBUTIONS-OF-GAINS>                       196,689
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                     18,573,681
<NUMBER-OF-SHARES-REDEEMED>                 13,062,080
<SHARES-REINVESTED>                          2,529,434
<NET-CHANGE-IN-ASSETS>                      99,231,730
<ACCUMULATED-NII-PRIOR>                      1,845,746
<ACCUMULATED-GAINS-PRIOR>                   (1,885,881)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        1,869,877
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              2,292,770
<AVERAGE-NET-ASSETS>                       415,149,919
<PER-SHARE-NAV-BEGIN>                            10.45
<PER-SHARE-NII>                                   0.69
<PER-SHARE-GAIN-APPREC>                           0.33
<PER-SHARE-DIVIDEND>                             (0.64)
<PER-SHARE-DISTRIBUTIONS>                        (0.02)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              10.81
<EXPENSE-RATIO>                                   0.54
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 51
   <NAME> Value Equity Fund, Class 1
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                    2,076,604,643
<INVESTMENTS-AT-VALUE>                   3,196,022,295
<RECEIVABLES>                               25,964,969
<ASSETS-OTHER>                                   5,510
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                           3,221,992,774
<PAYABLE-FOR-SECURITIES>                    11,451,815
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                   12,096,321
<TOTAL-LIABILITIES>                         23,548,136
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                 2,027,869,764
<SHARES-COMMON-STOCK>                           11,555
<SHARES-COMMON-PRIOR>                           10,640
<ACCUMULATED-NII-CURRENT>                    1,297,337
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                     49,859,885
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                 1,119,417,652
<NET-ASSETS>                                   196,012
<DIVIDEND-INCOME>                                4,320
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   2,961
<NET-INVESTMENT-INCOME>                          1,359
<REALIZED-GAINS-CURRENT>                        16,004
<APPREC-INCREASE-CURRENT>                       25,043
<NET-CHANGE-FROM-OPS>                           42,406
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        1,299
<DISTRIBUTIONS-OF-GAINS>                        13,946
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                915
<NET-CHANGE-IN-ASSETS>                          42,405
<ACCUMULATED-NII-PRIOR>                        410,862
<ACCUMULATED-GAINS-PRIOR>                   14,178,355
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                       13,063,454
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                             16,005,585
<AVERAGE-NET-ASSETS>                           176,265
<PER-SHARE-NAV-BEGIN>                            14.44
<PER-SHARE-NII>                                   0.13
<PER-SHARE-GAIN-APPREC>                           3.81
<PER-SHARE-DIVIDEND>                             (0.12)
<PER-SHARE-DISTRIBUTIONS>                        (1.30)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              16.96
<EXPENSE-RATIO>                                   1.68
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 52
   <NAME> Value Equity Fund, Class 2
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                    2,076,604,643
<INVESTMENTS-AT-VALUE>                   3,196,022,295
<RECEIVABLES>                               25,964,969
<ASSETS-OTHER>                                   5,510
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                           3,221,992,774
<PAYABLE-FOR-SECURITIES>                    11,451,815
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                   12,096,321
<TOTAL-LIABILITIES>                         23,548,136
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                 2,027,869,764
<SHARES-COMMON-STOCK>                           11,719
<SHARES-COMMON-PRIOR>                           10,740
<ACCUMULATED-NII-CURRENT>                    1,297,337
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                     49,859,885
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                 1,119,417,652
<NET-ASSETS>                                   199,451
<DIVIDEND-INCOME>                                4,383
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   2,021
<NET-INVESTMENT-INCOME>                          2,362
<REALIZED-GAINS-CURRENT>                        16,248
<APPREC-INCREASE-CURRENT>                       25,395
<NET-CHANGE-FROM-OPS>                           44,005
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        2,285
<DISTRIBUTIONS-OF-GAINS>                        14,077
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                979
<NET-CHANGE-IN-ASSETS>                          44,005
<ACCUMULATED-NII-PRIOR>                        410,862
<ACCUMULATED-GAINS-PRIOR>                   14,178,355
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                       13,063,454
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                             16,005,585
<AVERAGE-NET-ASSETS>                           178,882
<PER-SHARE-NAV-BEGIN>                            14.47
<PER-SHARE-NII>                                   0.22
<PER-SHARE-GAIN-APPREC>                           3.84
<PER-SHARE-DIVIDEND>                             (0.21)
<PER-SHARE-DISTRIBUTIONS>                        (1.30)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              17.02
<EXPENSE-RATIO>                                   1.13
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 53
   <NAME> Value Equity Fund, Class 3
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                    2,076,604,643
<INVESTMENTS-AT-VALUE>                   3,196,022,295
<RECEIVABLES>                               25,964,969
<ASSETS-OTHER>                                   5,510
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                           3,221,992,774
<PAYABLE-FOR-SECURITIES>                    11,451,815
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                   12,096,321
<TOTAL-LIABILITIES>                         23,548,136
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                 2,027,869,764
<SHARES-COMMON-STOCK>                           11,813
<SHARES-COMMON-PRIOR>                           10,793
<ACCUMULATED-NII-CURRENT>                    1,297,337
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                     49,859,885
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                 1,119,417,652
<NET-ASSETS>                                   201,310
<DIVIDEND-INCOME>                                4,417
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,410
<NET-INVESTMENT-INCOME>                          3,007
<REALIZED-GAINS-CURRENT>                        16,375
<APPREC-INCREASE-CURRENT>                       25,577
<NET-CHANGE-FROM-OPS>                           44,959
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        2,920
<DISTRIBUTIONS-OF-GAINS>                        14,146
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                              1,020
<NET-CHANGE-IN-ASSETS>                          44,959
<ACCUMULATED-NII-PRIOR>                        410,862
<ACCUMULATED-GAINS-PRIOR>                   14,178,355
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                       13,063,454
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                             16,005,585
<AVERAGE-NET-ASSETS>                           180,246
<PER-SHARE-NAV-BEGIN>                            14.49
<PER-SHARE-NII>                                   0.28
<PER-SHARE-GAIN-APPREC>                           3.84
<PER-SHARE-DIVIDEND>                             (0.27)
<PER-SHARE-DISTRIBUTIONS>                        (1.30)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              17.04
<EXPENSE-RATIO>                                   0.78
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 54
   <NAME> Value Equity Fund, Class S
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                    2,076,604,643
<INVESTMENTS-AT-VALUE>                   3,196,022,295
<RECEIVABLES>                               25,964,969
<ASSETS-OTHER>                                   5,510
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                           3,221,992,774
<PAYABLE-FOR-SECURITIES>                    11,451,815
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                   12,096,321
<TOTAL-LIABILITIES>                         23,548,136
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                 2,027,869,764
<SHARES-COMMON-STOCK>                      188,089,578
<SHARES-COMMON-PRIOR>                      171,928,663
<ACCUMULATED-NII-CURRENT>                    1,297,337
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                     49,859,885
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                 1,119,417,652
<NET-ASSETS>                             3,197,847,865
<DIVIDEND-INCOME>                           71,105,548
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                              15,608,178
<NET-INVESTMENT-INCOME>                     55,497,370
<REALIZED-GAINS-CURRENT>                   263,861,492
<APPREC-INCREASE-CURRENT>                  407,483,711
<NET-CHANGE-FROM-OPS>                      726,842,573
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                   54,611,119
<DISTRIBUTIONS-OF-GAINS>                   228,186,420
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                     42,809,442
<NUMBER-OF-SHARES-REDEEMED>                 43,586,898
<SHARES-REINVESTED>                         16,938,371
<NET-CHANGE-IN-ASSETS>                     712,105,034
<ACCUMULATED-NII-PRIOR>                        410,862
<ACCUMULATED-GAINS-PRIOR>                   14,178,355
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                       13,063,454
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                             16,005,585
<AVERAGE-NET-ASSETS>                     2,902,454,365
<PER-SHARE-NAV-BEGIN>                            14.46
<PER-SHARE-NII>                                   0.32
<PER-SHARE-GAIN-APPREC>                           3.83
<PER-SHARE-DIVIDEND>                             (0.31)
<PER-SHARE-DISTRIBUTIONS>                        (1.30)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              17.00
<EXPENSE-RATIO>                                   0.54
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 11
   <NAME> Prime Fund, Class 1
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      228,230,839
<INVESTMENTS-AT-VALUE>                     228,209,681
<RECEIVABLES>                               15,760,118
<ASSETS-OTHER>                                     881
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             243,970,680
<PAYABLE-FOR-SECURITIES>                             0
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    2,252,213
<TOTAL-LIABILITIES>                          2,252,213
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   241,757,785
<SHARES-COMMON-STOCK>                              758
<SHARES-COMMON-PRIOR>                              727
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                        (18,160)
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                       (21,158)
<NET-ASSETS>                                   114,315
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                                6,476
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,871
<NET-INVESTMENT-INCOME>                          4,605
<REALIZED-GAINS-CURRENT>                            (5)
<APPREC-INCREASE-CURRENT>                           (8)
<NET-CHANGE-FROM-OPS>                            4,592
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        4,723
<DISTRIBUTIONS-OF-GAINS>                             0
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                 31
<NET-CHANGE-IN-ASSETS>                           4,591
<ACCUMULATED-NII-PRIOR>                         80,676
<ACCUMULATED-GAINS-PRIOR>                       (7,151)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        1,155,353
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              1,418,216
<AVERAGE-NET-ASSETS>                           111,962
<PER-SHARE-NAV-BEGIN>                           151.03
<PER-SHARE-NII>                                   6.33
<PER-SHARE-GAIN-APPREC>                          (0.01)
<PER-SHARE-DIVIDEND>                             (6.50)
<PER-SHARE-DISTRIBUTIONS>                         0.00
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                             150.85
<EXPENSE-RATIO>                                   1.67
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 12
   <NAME> Prime Fund, Class 2
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      228,230,839
<INVESTMENTS-AT-VALUE>                     228,209,681
<RECEIVABLES>                               15,760,118
<ASSETS-OTHER>                                     881
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             243,970,680
<PAYABLE-FOR-SECURITIES>                             0
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    2,252,213
<TOTAL-LIABILITIES>                          2,252,213
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   241,757,785
<SHARES-COMMON-STOCK>                              770
<SHARES-COMMON-PRIOR>                              734
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                        (18,160)
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                       (21,158)
<NET-ASSETS>                                   116,323
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                                6,572
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,274
<NET-INVESTMENT-INCOME>                          5,298
<REALIZED-GAINS-CURRENT>                            (5)
<APPREC-INCREASE-CURRENT>                           (9)
<NET-CHANGE-FROM-OPS>                            5,284
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        5,393
<DISTRIBUTIONS-OF-GAINS>                             0
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                 36
<NET-CHANGE-IN-ASSETS>                           5,284
<ACCUMULATED-NII-PRIOR>                         80,676
<ACCUMULATED-GAINS-PRIOR>                       (7,151)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        1,155,353
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              1,418,216
<AVERAGE-NET-ASSETS>                           113,614
<PER-SHARE-NAV-BEGIN>                           151.23
<PER-SHARE-NII>                                   7.22
<PER-SHARE-GAIN-APPREC>                          (0.03)
<PER-SHARE-DIVIDEND>                             (7.34)
<PER-SHARE-DISTRIBUTIONS>                         0.00
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                             151.08
<EXPENSE-RATIO>                                   1.12
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 13
   <NAME> Prime Fund, Class 3
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      228,230,839
<INVESTMENTS-AT-VALUE>                     228,209,681
<RECEIVABLES>                               15,760,118
<ASSETS-OTHER>                                     881
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             243,970,680
<PAYABLE-FOR-SECURITIES>                             0
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    2,252,213
<TOTAL-LIABILITIES>                          2,252,213
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   241,757,785
<SHARES-COMMON-STOCK>                              777
<SHARES-COMMON-PRIOR>                              738
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                        (18,160)
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                       (21,158)
<NET-ASSETS>                                   117,416
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                                6,622
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                     886
<NET-INVESTMENT-INCOME>                          5,736
<REALIZED-GAINS-CURRENT>                            (5)
<APPREC-INCREASE-CURRENT>                           (9)
<NET-CHANGE-FROM-OPS>                            5,722
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        5,838
<DISTRIBUTIONS-OF-GAINS>                             0
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                 39
<NET-CHANGE-IN-ASSETS>                           5,722
<ACCUMULATED-NII-PRIOR>                         80,676
<ACCUMULATED-GAINS-PRIOR>                       (7,151)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        1,155,353
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              1,418,216
<AVERAGE-NET-ASSETS>                           114,482
<PER-SHARE-NAV-BEGIN>                           151.29
<PER-SHARE-NII>                                   7.77
<PER-SHARE-GAIN-APPREC>                          (0.02)
<PER-SHARE-DIVIDEND>                             (7.91)
<PER-SHARE-DISTRIBUTIONS>                         0.00
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                             151.13
<EXPENSE-RATIO>                                   0.77
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 14
   <NAME> Prime Fund, Class S
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      228,230,839
<INVESTMENTS-AT-VALUE>                     228,209,681
<RECEIVABLES>                               15,760,118
<ASSETS-OTHER>                                     881
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             243,970,680
<PAYABLE-FOR-SECURITIES>                             0
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    2,252,213
<TOTAL-LIABILITIES>                          2,252,213
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   241,757,785
<SHARES-COMMON-STOCK>                        1,600,181
<SHARES-COMMON-PRIOR>                        1,713,474
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                        (18,160)
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                       (21,158)
<NET-ASSETS>                               241,370,413
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                           14,852,911
<OTHER-INCOME>                                       0
<EXPENSES-NET>                               1,384,427
<NET-INVESTMENT-INCOME>                     13,468,484
<REALIZED-GAINS-CURRENT>                       (10,994)
<APPREC-INCREASE-CURRENT>                      (13,044)
<NET-CHANGE-FROM-OPS>                       13,444,446
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                   13,552,104
<DISTRIBUTIONS-OF-GAINS>                             0
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                      2,313,757
<NUMBER-OF-SHARES-REDEEMED>                  2,516,899
<SHARES-REINVESTED>                             89,849
<NET-CHANGE-IN-ASSETS>                     (17,358,611)
<ACCUMULATED-NII-PRIOR>                         80,676
<ACCUMULATED-GAINS-PRIOR>                       (7,151)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        1,155,353
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              1,418,216
<AVERAGE-NET-ASSETS>                       256,404,274
<PER-SHARE-NAV-BEGIN>                           151.00
<PER-SHARE-NII>                                   8.14
<PER-SHARE-GAIN-APPREC>                          (0.01)
<PER-SHARE-DIVIDEND>                             (8.29)
<PER-SHARE-DISTRIBUTIONS>                         0.00
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                             150.84
<EXPENSE-RATIO>                                   0.54
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 61
   <NAME> Small CAP Value Equity Fund, Class 1
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      458,944,857
<INVESTMENTS-AT-VALUE>                     686,758,593
<RECEIVABLES>                                4,999,796
<ASSETS-OTHER>                                  22,236
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             691,780,625
<PAYABLE-FOR-SECURITIES>                             0
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                      815,968
<TOTAL-LIABILITIES>                            815,968
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   460,933,162
<SHARES-COMMON-STOCK>                           11,677
<SHARES-COMMON-PRIOR>                           10,666
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                      2,217,759
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                   227,813,736
<NET-ASSETS>                                   192,471
<DIVIDEND-INCOME>                                2,530
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   2,942
<NET-INVESTMENT-INCOME>                           (412)
<REALIZED-GAINS-CURRENT>                        16,150
<APPREC-INCREASE-CURRENT>                       33,921
<NET-CHANGE-FROM-OPS>                           49,659
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                            0
<DISTRIBUTIONS-OF-GAINS>                        16,515
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                              1,011
<NET-CHANGE-IN-ASSETS>                          49,658
<ACCUMULATED-NII-PRIOR>                        192,363
<ACCUMULATED-GAINS-PRIOR>                    4,972,374
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        3,149,017
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              3,733,206
<AVERAGE-NET-ASSETS>                           165,613
<PER-SHARE-NAV-BEGIN>                            13.39
<PER-SHARE-NII>                                  (0.04)
<PER-SHARE-GAIN-APPREC>                           4.67
<PER-SHARE-DIVIDEND>                              0.00
<PER-SHARE-DISTRIBUTIONS>                        (1.54)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              16.48
<EXPENSE-RATIO>                                   1.78
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 62
   <NAME> Small CAP Value Equity Fund, Class 2
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      458,944,857
<INVESTMENTS-AT-VALUE>                     686,758,593
<RECEIVABLES>                                4,999,796
<ASSETS-OTHER>                                  22,236
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             691,780,625
<PAYABLE-FOR-SECURITIES>                             0
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                      815,968
<TOTAL-LIABILITIES>                            815,968
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   460,933,162
<SHARES-COMMON-STOCK>                           11,809
<SHARES-COMMON-PRIOR>                           10,767
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                      2,217,759
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                   227,813,736
<NET-ASSETS>                                   195,879
<DIVIDEND-INCOME>                                2,568
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   2,062
<NET-INVESTMENT-INCOME>                            506
<REALIZED-GAINS-CURRENT>                        16,393
<APPREC-INCREASE-CURRENT>                       34,434
<NET-CHANGE-FROM-OPS>                           51,333
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                          449
<DISTRIBUTIONS-OF-GAINS>                        16,672
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                              1,042
<NET-CHANGE-IN-ASSETS>                          51,334
<ACCUMULATED-NII-PRIOR>                        192,363
<ACCUMULATED-GAINS-PRIOR>                    4,972,374
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        3,149,017
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              3,733,206
<AVERAGE-NET-ASSETS>                           168,111
<PER-SHARE-NAV-BEGIN>                            13.42
<PER-SHARE-NII>                                   0.05
<PER-SHARE-GAIN-APPREC>                           4.70
<PER-SHARE-DIVIDEND>                             (0.04)
<PER-SHARE-DISTRIBUTIONS>                        (1.54)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              16.59
<EXPENSE-RATIO>                                   1.23
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 63
   <NAME> Small CAP Value Equity Fund, Class 3
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      458,944,857
<INVESTMENTS-AT-VALUE>                     686,758,593
<RECEIVABLES>                                4,999,796
<ASSETS-OTHER>                                  22,236
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             691,780,625
<PAYABLE-FOR-SECURITIES>                             0
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                      815,968
<TOTAL-LIABILITIES>                            815,968
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   460,933,162
<SHARES-COMMON-STOCK>                           11,922
<SHARES-COMMON-PRIOR>                           10,837
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                      2,217,759
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                   227,813,736
<NET-ASSETS>                                   198,007
<DIVIDEND-INCOME>                                2,592
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,491
<NET-INVESTMENT-INCOME>                          1,101
<REALIZED-GAINS-CURRENT>                        16,544
<APPREC-INCREASE-CURRENT>                       34,753
<NET-CHANGE-FROM-OPS>                           52,398
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        1,067
<DISTRIBUTIONS-OF-GAINS>                        16,782
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                              1,085
<NET-CHANGE-IN-ASSETS>                          52,398
<ACCUMULATED-NII-PRIOR>                        192,363
<ACCUMULATED-GAINS-PRIOR>                    4,972,374
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        3,149,017
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              3,733,206
<AVERAGE-NET-ASSETS>                           169,660
<PER-SHARE-NAV-BEGIN>                            13.44
<PER-SHARE-NII>                                   0.10
<PER-SHARE-GAIN-APPREC>                           4.71
<PER-SHARE-DIVIDEND>                             (0.10)
<PER-SHARE-DISTRIBUTIONS>                        (1.54)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              16.61
<EXPENSE-RATIO>                                   0.88
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 64
   <NAME> Small CAP Value Equity Fund, Class S
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      458,944,857
<INVESTMENTS-AT-VALUE>                     686,758,593
<RECEIVABLES>                                4,999,796
<ASSETS-OTHER>                                  22,236
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             691,780,625
<PAYABLE-FOR-SECURITIES>                             0
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                      815,968
<TOTAL-LIABILITIES>                            815,968
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   460,933,162
<SHARES-COMMON-STOCK>                       41,565,529
<SHARES-COMMON-PRIOR>                       34,013,589
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                      2,217,759
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                   227,813,736
<NET-ASSETS>                               690,378,300
<DIVIDEND-INCOME>                            8,736,205
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                               3,661,040
<NET-INVESTMENT-INCOME>                      5,075,165
<REALIZED-GAINS-CURRENT>                    56,022,656
<APPREC-INCREASE-CURRENT>                  116,301,060
<NET-CHANGE-FROM-OPS>                      177,398,881
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                    5,267,208
<DISTRIBUTIONS-OF-GAINS>                    58,776,388
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                     14,575,709
<NUMBER-OF-SHARES-REDEEMED>                 10,914,681
<SHARES-REINVESTED>                          3,890,912
<NET-CHANGE-IN-ASSETS>                     233,442,884
<ACCUMULATED-NII-PRIOR>                        192,363
<ACCUMULATED-GAINS-PRIOR>                    4,972,374
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        3,149,017
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              3,733,206
<AVERAGE-NET-ASSETS>                       572,045,167
<PER-SHARE-NAV-BEGIN>                            13.43
<PER-SHARE-NII>                                   0.13
<PER-SHARE-GAIN-APPREC>                           4.73
<PER-SHARE-DIVIDEND>                             (0.14)
<PER-SHARE-DISTRIBUTIONS>                        (1.54)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              16.61
<EXPENSE-RATIO>                                   0.64
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 41
   <NAME> Balanced Fund, Class 1
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      521,248,374
<INVESTMENTS-AT-VALUE>                     660,409,911
<RECEIVABLES>                                4,944,936
<ASSETS-OTHER>                                   1,001
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             665,355,848
<PAYABLE-FOR-SECURITIES>                     1,385,886
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    8,356,831
<TOTAL-LIABILITIES>                          9,742,717
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   510,255,546
<SHARES-COMMON-STOCK>                           11,560
<SHARES-COMMON-PRIOR>                           10,838
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                      6,196,048
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                   139,161,537
<NET-ASSETS>                                   156,975
<DIVIDEND-INCOME>                                5,992
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   2,442
<NET-INVESTMENT-INCOME>                          3,550
<REALIZED-GAINS-CURRENT>                         7,116
<APPREC-INCREASE-CURRENT>                       12,488
<NET-CHANGE-FROM-OPS>                           23,154
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        3,540
<DISTRIBUTIONS-OF-GAINS>                         6,158
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                722
<NET-CHANGE-IN-ASSETS>                          23,154
<ACCUMULATED-NII-PRIOR>                         26,102
<ACCUMULATED-GAINS-PRIOR>                    1,920,993
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        2,799,328
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              3,430,229
<AVERAGE-NET-ASSETS>                           145,791
<PER-SHARE-NAV-BEGIN>                            12.35
<PER-SHARE-NII>                                   0.33
<PER-SHARE-GAIN-APPREC>                           1.80
<PER-SHARE-DIVIDEND>                             (0.33)
<PER-SHARE-DISTRIBUTIONS>                        (0.57)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              13.58
<EXPENSE-RATIO>                                   1.68
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 42
   <NAME> Balanced Fund, Class 2
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      521,248,374
<INVESTMENTS-AT-VALUE>                     660,409,911
<RECEIVABLES>                                4,944,936
<ASSETS-OTHER>                                   1,001
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             665,355,848
<PAYABLE-FOR-SECURITIES>                     1,385,886
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    8,356,831
<TOTAL-LIABILITIES>                          9,742,717
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   510,255,546
<SHARES-COMMON-STOCK>                           11,735
<SHARES-COMMON-PRIOR>                           10,948
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                      6,196,048
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                   139,161,537
<NET-ASSETS>                                   159,724
<DIVIDEND-INCOME>                                6,081
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,664
<NET-INVESTMENT-INCOME>                          4,417
<REALIZED-GAINS-CURRENT>                         7,225
<APPREC-INCREASE-CURRENT>                       12,665
<NET-CHANGE-FROM-OPS>                           24,307
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        4,381
<DISTRIBUTIONS-OF-GAINS>                         6,204
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                787
<NET-CHANGE-IN-ASSETS>                          24,306
<ACCUMULATED-NII-PRIOR>                         26,102
<ACCUMULATED-GAINS-PRIOR>                    1,920,993
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        2,799,328
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              3,430,229
<AVERAGE-NET-ASSETS>                           147,944
<PER-SHARE-NAV-BEGIN>                            12.37
<PER-SHARE-NII>                                   0.40
<PER-SHARE-GAIN-APPREC>                           1.81
<PER-SHARE-DIVIDEND>                             (0.40)
<PER-SHARE-DISTRIBUTIONS>                        (0.57)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              13.61
<EXPENSE-RATIO>                                   1.12
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 43
   <NAME> Balanced Fund, Class 3
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      521,248,374
<INVESTMENTS-AT-VALUE>                     660,409,911
<RECEIVABLES>                                4,944,936
<ASSETS-OTHER>                                   1,001
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             665,355,848
<PAYABLE-FOR-SECURITIES>                     1,385,886
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    8,356,831
<TOTAL-LIABILITIES>                          9,742,717
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   510,255,546
<SHARES-COMMON-STOCK>                           11,820
<SHARES-COMMON-PRIOR>                           10,994
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                      6,196,048
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                   139,161,537
<NET-ASSETS>                                   161,227
<DIVIDEND-INCOME>                                6,127
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,159
<NET-INVESTMENT-INCOME>                          4,968
<REALIZED-GAINS-CURRENT>                         7,283
<APPREC-INCREASE-CURRENT>                       12,757
<NET-CHANGE-FROM-OPS>                           25,008
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        4,913
<DISTRIBUTIONS-OF-GAINS>                         6,230
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                826
<NET-CHANGE-IN-ASSETS>                          25,009
<ACCUMULATED-NII-PRIOR>                         26,102
<ACCUMULATED-GAINS-PRIOR>                    1,920,993
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        2,799,328
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              3,430,229
<AVERAGE-NET-ASSETS>                           149,082
<PER-SHARE-NAV-BEGIN>                            12.39
<PER-SHARE-NII>                                   0.45
<PER-SHARE-GAIN-APPREC>                           1.82
<PER-SHARE-DIVIDEND>                             (0.45)
<PER-SHARE-DISTRIBUTIONS>                        (0.57)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              13.64
<EXPENSE-RATIO>                                   0.78
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 44
   <NAME> Balanced Fund, Class S
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      521,248,374
<INVESTMENTS-AT-VALUE>                     660,409,911
<RECEIVABLES>                                4,944,936
<ASSETS-OTHER>                                   1,001
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             665,355,848
<PAYABLE-FOR-SECURITIES>                     1,385,886
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    8,356,831
<TOTAL-LIABILITIES>                          9,742,717
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   510,255,546
<SHARES-COMMON-STOCK>                       48,223,502
<SHARES-COMMON-PRIOR>                       45,632,444
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                      6,196,048
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                   139,161,537
<NET-ASSETS>                               655,135,205
<DIVIDEND-INCOME>                           25,545,807
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                               3,349,970
<NET-INVESTMENT-INCOME>                     22,195,837
<REALIZED-GAINS-CURRENT>                    30,454,072
<APPREC-INCREASE-CURRENT>                   53,030,679
<NET-CHANGE-FROM-OPS>                      105,680,588
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                   22,163,635
<DISTRIBUTIONS-OF-GAINS>                    26,240,454
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                     15,490,780
<NUMBER-OF-SHARES-REDEEMED>                 16,501,676
<SHARES-REINVESTED>                          3,601,954
<NET-CHANGE-IN-ASSETS>                      91,854,814
<ACCUMULATED-NII-PRIOR>                         26,102
<ACCUMULATED-GAINS-PRIOR>                    1,920,993
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        2,799,328
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              3,430,229
<AVERAGE-NET-ASSETS>                       621,630,134
<PER-SHARE-NAV-BEGIN>                            12.34
<PER-SHARE-NII>                                   0.48
<PER-SHARE-GAIN-APPREC>                           1.82
<PER-SHARE-DIVIDEND>                             (0.48)
<PER-SHARE-DISTRIBUTIONS>                        (0.57)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              13.59
<EXPENSE-RATIO>                                   0.54
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 71
   <NAME> International Equity Fund, Class 1
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      490,229,315
<INVESTMENTS-AT-VALUE>                     548,946,384
<RECEIVABLES>                               27,331,512
<ASSETS-OTHER>                                 200,916
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             576,478,812
<PAYABLE-FOR-SECURITIES>                     4,293,610
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                   25,003,268
<TOTAL-LIABILITIES>                         29,296,878
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   469,631,790
<SHARES-COMMON-STOCK>                           10,526
<SHARES-COMMON-PRIOR>                           10,176
<ACCUMULATED-NII-CURRENT>                      293,037
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                     16,328,165
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                    60,928,942
<NET-ASSETS>                                   128,942
<DIVIDEND-INCOME>                                2,000
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   2,769
<NET-INVESTMENT-INCOME>                           (769)
<REALIZED-GAINS-CURRENT>                        11,612
<APPREC-INCREASE-CURRENT>                        5,419
<NET-CHANGE-FROM-OPS>                           16,262
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                           91
<DISTRIBUTIONS-OF-GAINS>                         4,184
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                350
<NET-CHANGE-IN-ASSETS>                          16,261
<ACCUMULATED-NII-PRIOR>                        113,978
<ACCUMULATED-GAINS-PRIOR>                  (12,355,482)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        4,149,537
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              5,271,207
<AVERAGE-NET-ASSETS>                           125,710
<PER-SHARE-NAV-BEGIN>                            11.07
<PER-SHARE-NII>                                  (0.07)
<PER-SHARE-GAIN-APPREC>                           1.67
<PER-SHARE-DIVIDEND>                             (0.01)
<PER-SHARE-DISTRIBUTIONS>                        (0.41)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              12.25
<EXPENSE-RATIO>                                   2.20
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 72
   <NAME> International Equity Fund, Class 2
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      490,229,315
<INVESTMENTS-AT-VALUE>                     548,946,384
<RECEIVABLES>                               27,331,512
<ASSETS-OTHER>                                 200,916
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             576,478,812
<PAYABLE-FOR-SECURITIES>                     4,293,610
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                   25,003,268
<TOTAL-LIABILITIES>                         29,296,878
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   469,631,790
<SHARES-COMMON-STOCK>                           10,635
<SHARES-COMMON-PRIOR>                           10,281
<ACCUMULATED-NII-CURRENT>                      293,037
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                     16,328,165
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                    60,928,942
<NET-ASSETS>                                   131,194
<DIVIDEND-INCOME>                                2,029
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   2,109
<NET-INVESTMENT-INCOME>                            (80)
<REALIZED-GAINS-CURRENT>                        11,791
<APPREC-INCREASE-CURRENT>                        5,463
<NET-CHANGE-FROM-OPS>                           17,174
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                          133
<DISTRIBUTIONS-OF-GAINS>                         4,229
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                354
<NET-CHANGE-IN-ASSETS>                          17,175
<ACCUMULATED-NII-PRIOR>                        113,978
<ACCUMULATED-GAINS-PRIOR>                  (12,355,482)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        4,149,537
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              5,271,207
<AVERAGE-NET-ASSETS>                           127,561
<PER-SHARE-NAV-BEGIN>                            11.09
<PER-SHARE-NII>                                  (0.01)
<PER-SHARE-GAIN-APPREC>                           1.68
<PER-SHARE-DIVIDEND>                             (0.01)
<PER-SHARE-DISTRIBUTIONS>                        (0.41)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              12.34
<EXPENSE-RATIO>                                   1.65
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 73
   <NAME> International Equity Fund, Class 3
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      490,229,315
<INVESTMENTS-AT-VALUE>                     548,946,384
<RECEIVABLES>                               27,331,512
<ASSETS-OTHER>                                 200,916
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             576,478,812
<PAYABLE-FOR-SECURITIES>                     4,293,610
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                   25,003,268
<TOTAL-LIABILITIES>                         29,296,878
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   469,631,790
<SHARES-COMMON-STOCK>                           10,680
<SHARES-COMMON-PRIOR>                           10,315
<ACCUMULATED-NII-CURRENT>                      293,037
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                     16,328,165
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                    60,928,942
<NET-ASSETS>                                   132,039
<DIVIDEND-INCOME>                                2,039
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,799
<NET-INVESTMENT-INCOME>                            240
<REALIZED-GAINS-CURRENT>                        11,856
<APPREC-INCREASE-CURRENT>                        5,475
<NET-CHANGE-FROM-OPS>                           17,571
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                          256
<DISTRIBUTIONS-OF-GAINS>                         4,243
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                365
<NET-CHANGE-IN-ASSETS>                          17,571
<ACCUMULATED-NII-PRIOR>                        113,978
<ACCUMULATED-GAINS-PRIOR>                  (12,355,482)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        4,149,537
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              5,271,207
<AVERAGE-NET-ASSETS>                           128,225
<PER-SHARE-NAV-BEGIN>                            11.10
<PER-SHARE-NII>                                   0.02
<PER-SHARE-GAIN-APPREC>                           1.67
<PER-SHARE-DIVIDEND>                             (0.02)
<PER-SHARE-DISTRIBUTIONS>                        (0.41)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              12.36
<EXPENSE-RATIO>                                   1.40
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 74
   <NAME> International Equity Fund, Class S
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      490,229,315
<INVESTMENTS-AT-VALUE>                     548,946,384
<RECEIVABLES>                               27,331,512
<ASSETS-OTHER>                                 200,916
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             576,478,812
<PAYABLE-FOR-SECURITIES>                     4,293,610
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                   25,003,268
<TOTAL-LIABILITIES>                         29,296,878
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   469,631,790
<SHARES-COMMON-STOCK>                       44,180,338
<SHARES-COMMON-PRIOR>                       32,070,618
<ACCUMULATED-NII-CURRENT>                      293,037
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                     16,328,165
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                    60,928,942
<NET-ASSETS>                               546,789,759
<DIVIDEND-INCOME>                            7,789,859
<INTEREST-INCOME>                                    0
<OTHER-INCOME>                                       0
<EXPENSES-NET>                               5,213,777
<NET-INVESTMENT-INCOME>                      2,576,082
<REALIZED-GAINS-CURRENT>                    46,807,308
<APPREC-INCREASE-CURRENT>                   13,009,849
<NET-CHANGE-FROM-OPS>                       62,393,239
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                    3,046,471
<DISTRIBUTIONS-OF-GAINS>                    17,495,727
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                     22,135,252
<NUMBER-OF-SHARES-REDEEMED>                 11,688,395
<SHARES-REINVESTED>                          1,662,863
<NET-CHANGE-IN-ASSETS>                     190,479,115
<ACCUMULATED-NII-PRIOR>                        113,978
<ACCUMULATED-GAINS-PRIOR>                  (12,355,482)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                        4,149,537
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                              5,271,207
<AVERAGE-NET-ASSETS>                       487,799,327
<PER-SHARE-NAV-BEGIN>                            11.11
<PER-SHARE-NII>                                   0.06
<PER-SHARE-GAIN-APPREC>                           1.69
<PER-SHARE-DIVIDEND>                             (0.07)
<PER-SHARE-DISTRIBUTIONS>                        (0.41)
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              12.38
<EXPENSE-RATIO>                                   1.06
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 21
   <NAME> Short Term Bond Fund, Class 1
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      205,430,337
<INVESTMENTS-AT-VALUE>                     206,723,676
<RECEIVABLES>                                4,578,048
<ASSETS-OTHER>                                  26,124
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             211,327,848
<PAYABLE-FOR-SECURITIES>                     9,055,799
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    1,630,762
<TOTAL-LIABILITIES>                         10,686,561
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   198,964,924
<SHARES-COMMON-STOCK>                           11,916
<SHARES-COMMON-PRIOR>                           11,415
<ACCUMULATED-NII-CURRENT>                       61,151
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                        321,873
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                     1,293,339
<NET-ASSETS>                                   122,436
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                                8,022
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,980
<NET-INVESTMENT-INCOME>                          6,042
<REALIZED-GAINS-CURRENT>                           424
<APPREC-INCREASE-CURRENT>                          108
<NET-CHANGE-FROM-OPS>                            6,574
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        5,130
<DISTRIBUTIONS-OF-GAINS>                            21
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                501
<NET-CHANGE-IN-ASSETS>                           6,573
<ACCUMULATED-NII-PRIOR>                         18,783
<ACCUMULATED-GAINS-PRIOR>                     (295,200)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                          769,014
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                                947,298
<AVERAGE-NET-ASSETS>                           118,583
<PER-SHARE-NAV-BEGIN>                            10.15
<PER-SHARE-NII>                                   0.53
<PER-SHARE-GAIN-APPREC>                           0.04
<PER-SHARE-DIVIDEND>                             (0.45)
<PER-SHARE-DISTRIBUTIONS>                         0.00
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              10.27
<EXPENSE-RATIO>                                   1.67
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 22
   <NAME> Short Term Bond Fund, Class 2
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      205,430,337
<INVESTMENTS-AT-VALUE>                     206,723,676
<RECEIVABLES>                                4,578,048
<ASSETS-OTHER>                                  26,124
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             211,327,848
<PAYABLE-FOR-SECURITIES>                     9,055,799
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    1,630,762
<TOTAL-LIABILITIES>                         10,686,561
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   198,964,924
<SHARES-COMMON-STOCK>                           12,115
<SHARES-COMMON-PRIOR>                           11,544
<ACCUMULATED-NII-CURRENT>                       61,151
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                        321,873
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                     1,293,339
<NET-ASSETS>                                   124,585
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                                8,140
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                   1,347
<NET-INVESTMENT-INCOME>                          6,793
<REALIZED-GAINS-CURRENT>                           431
<APPREC-INCREASE-CURRENT>                          112
<NET-CHANGE-FROM-OPS>                            7,336
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        5,845
<DISTRIBUTIONS-OF-GAINS>                            22
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                571
<NET-CHANGE-IN-ASSETS>                           7,335
<ACCUMULATED-NII-PRIOR>                         18,783
<ACCUMULATED-GAINS-PRIOR>                     (295,200)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                          769,014
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                                947,298
<AVERAGE-NET-ASSETS>                           120,334
<PER-SHARE-NAV-BEGIN>                            10.16
<PER-SHARE-NII>                                   0.59
<PER-SHARE-GAIN-APPREC>                           0.04
<PER-SHARE-DIVIDEND>                             (0.51)
<PER-SHARE-DISTRIBUTIONS>                         0.00
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              10.28
<EXPENSE-RATIO>                                   1.12
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 23
   <NAME> Short Term Bond Fund, Class 3
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      205,430,337
<INVESTMENTS-AT-VALUE>                     206,723,676
<RECEIVABLES>                                4,578,048
<ASSETS-OTHER>                                  26,124
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             211,327,848
<PAYABLE-FOR-SECURITIES>                     9,055,799
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    1,630,762
<TOTAL-LIABILITIES>                         10,686,561
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   198,964,924
<SHARES-COMMON-STOCK>                           12,213
<SHARES-COMMON-PRIOR>                           11,599
<ACCUMULATED-NII-CURRENT>                       61,151
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                        321,873
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                     1,293,339
<NET-ASSETS>                                   125,819
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                                8,206
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                     937
<NET-INVESTMENT-INCOME>                          7,269
<REALIZED-GAINS-CURRENT>                           435
<APPREC-INCREASE-CURRENT>                          113
<NET-CHANGE-FROM-OPS>                            7,817
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                        6,291
<DISTRIBUTIONS-OF-GAINS>                            22
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                          0
<SHARES-REINVESTED>                                614
<NET-CHANGE-IN-ASSETS>                           7,818
<ACCUMULATED-NII-PRIOR>                         18,783
<ACCUMULATED-GAINS-PRIOR>                     (295,200)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                          769,014
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                                947,298
<AVERAGE-NET-ASSETS>                           121,315
<PER-SHARE-NAV-BEGIN>                            10.17
<PER-SHARE-NII>                                   0.63
<PER-SHARE-GAIN-APPREC>                           0.04
<PER-SHARE-DIVIDEND>                             (0.54)
<PER-SHARE-DISTRIBUTIONS>                         0.00
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              10.30
<EXPENSE-RATIO>                                   0.77
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        


<TABLE> <S> <C>

<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds, Inc.
form N-SAR for the year ended December 31, 1997
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
   <NUMBER> 24
   <NAME> Short Term Bond Fund, Class S
       
<S>                            <C>
<PERIOD-TYPE>                           12-MOS
<FISCAL-YEAR-END>                          DEC-31-1997
<PERIOD-END>                               DEC-31-1997
<INVESTMENTS-AT-COST>                      205,430,337
<INVESTMENTS-AT-VALUE>                     206,723,676
<RECEIVABLES>                                4,578,048
<ASSETS-OTHER>                                  26,124
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                             211,327,848
<PAYABLE-FOR-SECURITIES>                     9,055,799
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    1,630,762
<TOTAL-LIABILITIES>                         10,686,561
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                   198,964,924
<SHARES-COMMON-STOCK>                       19,577,260
<SHARES-COMMON-PRIOR>                       14,365,202
<ACCUMULATED-NII-CURRENT>                       61,151
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                        321,873
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                     1,293,339
<NET-ASSETS>                               200,268,447
<DIVIDEND-INCOME>                                    0
<INTEREST-INCOME>                           11,525,758
<OTHER-INCOME>                                       0
<EXPENSES-NET>                                 924,788
<NET-INVESTMENT-INCOME>                     10,600,970
<REALIZED-GAINS-CURRENT>                       665,851
<APPREC-INCREASE-CURRENT>                      275,277
<NET-CHANGE-FROM-OPS>                       11,542,098
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                   10,576,607
<DISTRIBUTIONS-OF-GAINS>                        34,836
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                      9,428,262
<NUMBER-OF-SHARES-REDEEMED>                  5,254,453
<SHARES-REINVESTED>                          1,038,249
<NET-CHANGE-IN-ASSETS>                      55,086,152
<ACCUMULATED-NII-PRIOR>                         18,783
<ACCUMULATED-GAINS-PRIOR>                     (295,200)
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                          769,014
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                                947,298
<AVERAGE-NET-ASSETS>                       170,531,833
<PER-SHARE-NAV-BEGIN>                            10.11
<PER-SHARE-NII>                                   0.65
<PER-SHARE-GAIN-APPREC>                           0.04
<PER-SHARE-DIVIDEND>                             (0.57)
<PER-SHARE-DISTRIBUTIONS>                         0.00
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              10.23
<EXPENSE-RATIO>                                   0.54
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                              0.00
        






                        REPORT OF INDEPENDENT ACCOUNTANTS



To the Board of Trustees and Shareholders of the MassMutual Institutional Funds:

In planning and performing  our audit of the financial  statements and financial
highlights of the MassMutual Institutional Funds, comprising,  respectively, the
Prime,  Short-Term  Bond,  Core Bond,  Balanced,  Value Equity,  Small Cap Value
Equity,  and  International  Equity  Funds,  (the  "Funds"),  for the year ended
December 31, 1997, we considered its internal  control,  including  control over
safeguarding  securities,  in order to determine our auditing procedures for the
purpose of  expressing  our opinion on the  financial  statements  and financial
highlights  and to comply with the  requirements  of Form N-SAR,  not to provide
assurance on internal control.

The  management of the Funds is responsible  for  establishing  and  maintaining
internal control. In fulfilling this responsibility,  estimates and judgments by
management  are  required to assess the expected  benefits and related  costs of
controls.  Generally,  controls  that are  relevant  to an audit  pertain to the
entity's objective of preparing  financial  statements and financial  highlights
for external  purposes that are fairly  presented in conformity  with  generally
accepted  accounting  principles.  Those controls  include the  safeguarding  of
assets against unauthorized acquisition, use, or disposition.

Because of inherent limitations in internal controls,  errors or fraud may occur
and may not be detected.  Also, projection of any evaluation of internal control
to future periods is subject to the risk that it may become  inadequate  because
of changes in conditions or that the  effectiveness  of the design and operation
may deteriorate.

Our consideration of internal control would not necessarily disclose all matters
in  internal   control  that  might  be  material   weaknesses  under  standards
established  by the  American  Institute  of  Certified  Public  Accountants.  A
material  weakness  is a  condition  in which  the  design or  operation  of any
specific  internal  control  component does not reduce to a relatively low level
the risk that  errors or fraud in amounts  that would be material in relation to
the financial  statements and financial  highlights  being audited may occur and
not be detected  within a timely  period by  employees  in the normal  course of
performing  their assigned  functions.  However,  we noted no matters  involving
internal  control,  including  controls over  safeguarding  securities,  that we
consider to be material weaknesses as defined above as of December 31, 1997.

This report is intended solely for the information and use of management and the
Securities and Exchange Commission.


COOPERS & LYBRAND LLP


Springfield, Massachusetts
February 6, 1998



77I.     New or Amended Securities


Effective December 1, 1997, all class 4 shares of all Funds were redesignated as
Class S shares, and the expense structure was revised accordingly. Additionally,
two new  classes of  shares,  Class A and Class Y, were  created  for all Funds.
Effective  January 1, 1998, Class A and Y shares began  operations,  and Class 1
shares of all Funds  were  exchanged  for Class A shares and Class 2 and Class 3
shares of all Funds were exchanged for Class Y shares.  The Class 1, Class 2 and
Class 3 shares were subsequently  terminated by the Trustees. The new classes of
shares are offered to different  types of investors and have  different  expense
and sales charge structures.




77D.     Policies with respect to security investments


In order to increase investment flexibility,  the sector asset allocation ranges
for the Balanced  Fund were  replaced  with maximums for each sector as follows:
35% for the Prime and Core Bond sectors and 65% for the Value Equity sector. The
purpose of the change was to increase the Core Bond sector while  decreasing the
Prime sector.

The policy  limiting  the  amount of liquid  Rule 144A  securities  which may be
acquired by the Prime Fund, the Short-Term Bond Fund, the Core Bond Fund and the
Prime and Core sectors of the Balanced Fund to 5% of net assets was eliminated.

The registrant believe that each of the changes to the policies noted above were
not material.




                                                                    Exhibit 15.A

                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                      MASSMUTUAL PRIME FUND: CLASS A SHARES
                     -------------------------------------

                           SERVICE PLAN AND AGREEMENT



This Plan and Agreement (the "Plan") constitutes the Service Plan of the Class A
shares of the  MassMutual  Prime Fund (the "Fund"),  a series of the  MassMutual
Institutional  Funds, a  Massachusetts  business  trust (the  "Trust"),  adopted
pursuant to the  provisions  of Rule 12b-1 under the  Investment  Company Act of
1940 (the "Act") and the  related  agreement  between the Trust and  Oppenheimer
Funds  Distributor,  Inc., the principal  underwriter of the Trust's shares (the
"Distributor.")  During  the  effective  term of this  Plan,  the Trust may make
payments  to   Massachusetts   Mutual  Life   Insurance   Company,   the  Fund's
Administrator  ("MassMutual"),  upon the terms and  conditions  hereinafter  set
forth:

SECTION 1. The Trust will pay service fees to MassMutual  for services  provided
and expenses  incurred by it for purposes of maintaining  or providing  personal
services  to Class A  shareholders  (the  "Servicing  Fee").  The amount of such
payments  and the purposes  for which they are made shall be  determined  by the
Qualified  Trustees  (as  defined  below).  The  Servicing  Fee may be  spent by
MassMutual on account of personal  services  rendered to Class A shareholders of
the Fund  and/or  maintenance  of  Class A  shareholder  accounts.  MassMutual's
Servicing  Fee  expenditures   may  include,   but  shall  not  be  limited  to,
compensation  to, and expenses  (including  telephone and overhead  expenses) of
financial  consultants or other employees of MassMutual,  the Fund's Distributor
or Sub-Distributor,  pension consultants or participating or introducing brokers
and  other  financial   intermediaries   who  assist   investors  in  completing
application forms and selecting  dividend and other account options;  who aid in
the  process  of  purchase  or  redemption  requests  for  Class A shares or the
processing  of dividend  payments  with  respect to Class A shares;  who provide
information periodically to Class A shareholders showing their position in Class
A shares; who prepare, print and deliver prospectuses and shareholder reports to
prospective Class A shareholders;  who oversee compliance with federal and state
laws  pertaining  to the sale of Class A  shares;  who issue  confirmations  for
transactions by Class A shareholders;  who forward  communications from the Fund
to  Class A  shareholders;  who  render  advice  regarding  the  suitability  of
particular investment  opportunities offered by the Fund in light of shareholder
needs;  who provide and  maintain  elective  shareholder  services;  who furnish
shareholder  sub-accounting;  who provide and maintain pre-authorized investment
plans  for  Class  A  shareholders;  who  respond  to  inquiries  from  Class  A
shareholders relating to such services; and/or who provide such similar services
as permitted under applicable statutes, rules or regulations.

Payments  under this  Section 1 of the Plan shall not exceed in any fiscal  year
the annual rate of .25% of the Fund's average daily net assets  attributable  to
Class A shares.  A majority of the Qualified  Trustees may, at any time and from
time to time,  reduce the amount of such payments,  or may suspend the operation
of the Plan for such period or periods of time as they may determine.

SECTION  2. To the  extent  that any  payments  made by the Fund to  MassMutual,
including payment of management and administrative  fees, should be deemed to be
indirect  financing of any activity  primarily intended to result in the sale of
shares  issued by the Fund within the context of Rule 12b-1 under the Act,  then
such payments shall be deemed to be authorized by this Plan.

SECTION 3. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

                                       1


SECTION 4. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 3.

SECTION 5.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 6. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class A shares
of the Fund.

SECTION 7. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any penalty,  by vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class A shares of the Fund, on not
        more than 60 days' written  notice to any other party to the  agreement;
        and

        (b)   that such agreement shall terminate automatically in the event of
        its assignment.

SECTION  8. This Plan may not be  amended  to  increase  materially  the  amount
permitted  pursuant to Sections 1 hereof  without the  approval of a majority of
the outstanding Class A shares of the Fund, and all material  amendments to this
Plan shall be  approved  in the manner  provided  for  approval  of this Plan in
Section 3.

SECTION 9. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 10. A copy of the Agreement and  Declaration of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class A shares of the Fund.

Executed as of this 26th day of November, 1997.


MASSMUTUAL INSTITUTIONAL                MASSACHUSETTS MUTUAL LIFE
FUNDS ON BEHALF OF MASSMUTUAL           INSURANCE COMPANY
PRIME FUND


BY:                                     BY:
   --------------------------------        -------------------------------

                                       2


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                MASSMUTUAL SHORT-TERM BOND FUND: CLASS A SHARES
                -----------------------------------------------

                           SERVICE PLAN AND AGREEMENT


This Plan and Agreement (the "Plan") constitutes the Service Plan of the Class A
shares of the  MassMutual  Short-Term  Bond Fund (the  "Fund"),  a series of the
MassMutual  Institutional  Funds, a Massachusetts  business trust (the "Trust"),
adopted  pursuant to the provisions of Rule 12b-1 under the  Investment  Company
Act of 1940  (the  "Act")  and the  related  agreement  between  the  Trust  and
Oppenheimer Funds  Distributor,  Inc., the principal  underwriter of the Trust's
shares (the  "Distributor.")  During the effective  term of this Plan, the Trust
may make payments to  Massachusetts  Mutual Life Insurance  Company,  the Fund's
Administrator  ("MassMutual"),  upon the terms and  conditions  hereinafter  set
forth:

SECTION 1. The Trust will pay service fees to MassMutual  for services  provided
and expenses  incurred by it for purposes of maintaining  or providing  personal
services  to Class A  shareholders  (the  "Servicing  Fee").  The amount of such
payments  and the purposes  for which they are made shall be  determined  by the
Qualified  Trustees  (as  defined  below).  The  Servicing  Fee may be  spent by
MassMutual on account of personal  services  rendered to Class A shareholders of
the Fund  and/or  maintenance  of  Class A  shareholder  accounts.  MassMutual's
Servicing  Fee  expenditures   may  include,   but  shall  not  be  limited  to,
compensation  to, and expenses  (including  telephone and overhead  expenses) of
financial  consultants or other employees of MassMutual,  the Fund's Distributor
or Sub-Distributor,  pension consultants or participating or introducing brokers
and  other  financial   intermediaries   who  assist   investors  in  completing
application forms and selecting  dividend and other account options;  who aid in
the  process  of  purchase  or  redemption  requests  for  Class A shares or the
processing  of dividend  payments  with  respect to Class A shares;  who provide
information periodically to Class A shareholders showing their position in Class
A shares; who prepare, print and deliver prospectuses and shareholder reports to
prospective Class A shareholders;  who oversee compliance with federal and state
laws  pertaining  to the sale of Class A  shares;  who issue  confirmations  for
transactions by Class A shareholders;  who forward  communications from the Fund
to  Class A  shareholders;  who  render  advice  regarding  the  suitability  of
particular investment  opportunities offered by the Fund in light of shareholder
needs;  who provide and  maintain  elective  shareholder  services;  who furnish
shareholder  sub-accounting;  who provide and maintain pre-authorized investment
plans  for  Class  A  shareholders;  who  respond  to  inquiries  from  Class  A
shareholders relating to such services; and/or who provide such similar services
as permitted under applicable statutes, rules or regulations.

Payments  under this  Section 1 of the Plan shall not exceed in any fiscal  year
the annual rate of .25% of the Fund's average daily net assets  attributable  to
Class A shares.  A majority of the Qualified  Trustees may, at any time and from
time to time,  reduce the amount of such payments,  or may suspend the operation
of the Plan for such period or periods of time as they may determine.

SECTION  2. To the  extent  that any  payments  made by the Fund to  MassMutual,
including payment of management and administrative  fees, should be deemed to be
indirect  financing of any activity  primarily intended to result in the sale of
shares  issued by the Fund within the context of Rule 12b-1 under the Act,  then
such payments shall be deemed to be authorized by this Plan.

SECTION 3. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

                                       3


SECTION 4. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 3.

SECTION 5.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 6. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class A shares
of the Fund.

SECTION 7. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any penalty,  by vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class A shares of the Fund, on not
        more than 60 days' written  notice to any other party to the  agreement;
        and

        (b)   that such agreement shall terminate automatically in the event of
        its assignment.

SECTION  8. This Plan may not be  amended  to  increase  materially  the  amount
permitted  pursuant to Sections 1 hereof  without the  approval of a majority of
the outstanding Class A shares of the Fund, and all material  amendments to this
Plan shall be  approved  in the manner  provided  for  approval  of this Plan in
Section 3.

SECTION 9. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 10. A copy of the Agreement and  Declaration of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class A shares of the Fund.


Executed as of this 26th day of November, 1997.

MASSMUTUAL INSTITUTIONAL                MASSACHUSETTS MUTUAL LIFE
FUNDS ON BEHALF OF MASSMUTUAL           INSURANCE COMPANY
SHORT-TERM BOND FUND


BY:                                     BY:
   --------------------------------        -------------------------------

                                       4


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                   MASSMUTUAL CORE BOND FUND: CLASS A SHARES
                   -----------------------------------------

                           SERVICE PLAN AND AGREEMENT


This Plan and Agreement (the "Plan") constitutes the Service Plan of the Class A
shares of the MassMutual Core-Bond Fund (the "Fund"), a series of the MassMutual
Institutional  Funds, a  Massachusetts  business  trust (the  "Trust"),  adopted
pursuant to the  provisions  of Rule 12b-1 under the  Investment  Company Act of
1940 (the "Act") and the  related  agreement  between the Trust and  Oppenheimer
Funds  Distributor,  Inc., the principal  underwriter of the Trust's shares (the
"Distributor.")  During  the  effective  term of this  Plan,  the Trust may make
payments  to   Massachusetts   Mutual  Life   Insurance   Company,   the  Fund's
Administrator  ("MassMutual"),  upon the terms and  conditions  hereinafter  set
forth:

SECTION 1. The Trust will pay service fees to MassMutual  for services  provided
and expenses  incurred by it for purposes of maintaining  or providing  personal
services  to Class A  shareholders  (the  "Servicing  Fee").  The amount of such
payments  and the purposes  for which they are made shall be  determined  by the
Qualified  Trustees  (as  defined  below).  The  Servicing  Fee may be  spent by
MassMutual on account of personal  services  rendered to Class A shareholders of
the Fund  and/or  maintenance  of  Class A  shareholder  accounts.  MassMutual's
Servicing  Fee  expenditures   may  include,   but  shall  not  be  limited  to,
compensation  to, and expenses  (including  telephone and overhead  expenses) of
financial  consultants or other employees of MassMutual,  the Fund's Distributor
or Sub-Distributor,  pension consultants or participating or introducing brokers
and  other  financial   intermediaries   who  assist   investors  in  completing
application forms and selecting  dividend and other account options;  who aid in
the  process  of  purchase  or  redemption  requests  for  Class A shares or the
processing  of dividend  payments  with  respect to Class A shares;  who provide
information periodically to Class A shareholders showing their position in Class
A shares; who prepare, print and deliver prospectuses and shareholder reports to
prospective Class A shareholders;  who oversee compliance with federal and state
laws  pertaining  to the sale of Class A  shares;  who issue  confirmations  for
transactions by Class A shareholders;  who forward  communications from the Fund
to  Class A  shareholders;  who  render  advice  regarding  the  suitability  of
particular investment  opportunities offered by the Fund in light of shareholder
needs;  who provide and  maintain  elective  shareholder  services;  who furnish
shareholder  sub-accounting;  who provide and maintain pre-authorized investment
plans  for  Class  A  shareholders;  who  respond  to  inquiries  from  Class  A
shareholders relating to such services; and/or who provide such similar services
as permitted under applicable statutes, rules or regulations.

Payments  under this  Section 1 of the Plan shall not exceed in any fiscal  year
the annual rate of .25% of the Fund's average daily net assets  attributable  to
Class A shares.  A majority of the Qualified  Trustees may, at any time and from
time to time,  reduce the amount of such payments,  or may suspend the operation
of the Plan for such period or periods of time as they may determine.

SECTION  2. To the  extent  that any  payments  made by the Fund to  MassMutual,
including payment of management and administrative  fees, should be deemed to be
indirect  financing of any activity  primarily intended to result in the sale of
shares  issued by the Fund within the context of Rule 12b-1 under the Act,  then
such payments shall be deemed to be authorized by this Plan.

SECTION 3. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

                                       5


SECTION 4. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 3.

SECTION 5.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 6. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class A shares
of the Fund.

SECTION 7. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any penalty,  by vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class A shares of the Fund, on not
        more than 60 days' written  notice to any other party to the  agreement;
        and

        (b)   that such agreement shall terminate automatically in the event of
        its assignment.

SECTION  8. This Plan may not be  amended  to  increase  materially  the  amount
permitted  pursuant to Sections 1 hereof  without the  approval of a majority of
the outstanding Class A shares of the Fund, and all material  amendments to this
Plan shall be  approved  in the manner  provided  for  approval  of this Plan in
Section 3.

SECTION 9. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 10. A copy of the Agreement and  Declaration of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class A shares of the Fund.


Executed as of this 26th day of November, 1997.

MASSMUTUAL INSTITUTIONAL                MASSACHUSETTS MUTUAL LIFE
FUNDS ON BEHALF OF MASSMUTUAL           INSURANCE COMPANY
CORE BOND FUND


BY:                                     BY:
   --------------------------------        -------------------------------

                                       6


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                   MASSMUTUAL BALANCED FUND: CLASS A SHARES
                   ----------------------------------------

                           SERVICE PLAN AND AGREEMENT


This Plan and Agreement (the "Plan") constitutes the Service Plan of the Class A
shares of the MassMutual  Balanced Fund (the "Fund"), a series of the MassMutual
Institutional  Funds, a  Massachusetts  business  trust (the  "Trust"),  adopted
pursuant to the  provisions  of Rule 12b-1 under the  Investment  Company Act of
1940 (the "Act") and the  related  agreement  between the Trust and  Oppenheimer
Funds  Distributor,  Inc., the principal  underwriter of the Trust's shares (the
"Distributor.")  During  the  effective  term of this  Plan,  the Trust may make
payments  to   Massachusetts   Mutual  Life   Insurance   Company,   the  Fund's
Administrator  ("MassMutual"),  upon the terms and  conditions  hereinafter  set
forth:

SECTION 1. The Trust will pay service fees to MassMutual  for services  provided
and expenses  incurred by it for purposes of maintaining  or providing  personal
services  to Class A  shareholders  (the  "Servicing  Fee").  The amount of such
payments  and the purposes  for which they are made shall be  determined  by the
Qualified  Trustees  (as  defined  below).  The  Servicing  Fee may be  spent by
MassMutual on account of personal  services  rendered to Class A shareholders of
the Fund  and/or  maintenance  of  Class A  shareholder  accounts.  MassMutual's
Servicing  Fee  expenditures   may  include,   but  shall  not  be  limited  to,
compensation  to, and expenses  (including  telephone and overhead  expenses) of
financial  consultants or other employees of MassMutual,  the Fund's Distributor
or Sub-Distributor,  pension consultants or participating or introducing brokers
and  other  financial   intermediaries   who  assist   investors  in  completing
application forms and selecting  dividend and other account options;  who aid in
the  process  of  purchase  or  redemption  requests  for  Class A shares or the
processing  of dividend  payments  with  respect to Class A shares;  who provide
information periodically to Class A shareholders showing their position in Class
A shares; who prepare, print and deliver prospectuses and shareholder reports to
prospective Class A shareholders;  who oversee compliance with federal and state
laws  pertaining  to the sale of Class A  shares;  who issue  confirmations  for
transactions by Class A shareholders;  who forward  communications from the Fund
to  Class A  shareholders;  who  render  advice  regarding  the  suitability  of
particular investment  opportunities offered by the Fund in light of shareholder
needs;  who provide and  maintain  elective  shareholder  services;  who furnish
shareholder  sub-accounting;  who provide and maintain pre-authorized investment
plans  for  Class  A  shareholders;  who  respond  to  inquiries  from  Class  A
shareholders relating to such services; and/or who provide such similar services
as permitted under applicable statutes, rules or regulations.

Payments  under this  Section 1 of the Plan shall not exceed in any fiscal  year
the annual rate of .25% of the Fund's average daily net assets  attributable  to
Class A shares.  A majority of the Qualified  Trustees may, at any time and from
time to time,  reduce the amount of such payments,  or may suspend the operation
of the Plan for such period or periods of time as they may determine.

SECTION  2. To the  extent  that any  payments  made by the Fund to  MassMutual,
including payment of management and administrative  fees, should be deemed to be
indirect  financing of any activity  primarily intended to result in the sale of
shares  issued by the Fund within the context of Rule 12b-1 under the Act,  then
such payments shall be deemed to be authorized by this Plan.

SECTION 3. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

                                       7


SECTION 4. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 3.

SECTION 5.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 6. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class A shares
of the Fund.

SECTION 7. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any penalty,  by vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class A shares of the Fund, on not
        more than 60 days' written  notice to any other party to the  agreement;
        and

        (b)   that such agreement shall terminate automatically in the event of
        its assignment.

SECTION  8. This Plan may not be  amended  to  increase  materially  the  amount
permitted  pursuant to Sections 1 hereof  without the  approval of a majority of
the outstanding Class A shares of the Fund, and all material  amendments to this
Plan shall be  approved  in the manner  provided  for  approval  of this Plan in
Section 3.

SECTION 9. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 10. A copy of the Agreement and  Declaration of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class A shares of the Fund.

Executed as of this 26th day of November, 1997.

MASSMUTUAL INSTITUTIONAL                MASSACHUSETTS MUTUAL LIFE
FUNDS ON BEHALF OF MASSMUTUAL           INSURANCE COMPANY
BALANCED FUND


BY:                                     BY:
   --------------------------------        -------------------------------

                                       8


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                 MASSMUTUAL VALUE EQUITY FUND: CLASS A SHARES
                 --------------------------------------------

                           SERVICE PLAN AND AGREEMENT


This Plan and Agreement (the "Plan") constitutes the Service Plan of the Class A
shares  of the  MassMutual  Value  Equity  Fund  (the  "Fund"),  a series of the
MassMutual  Institutional  Funds, a Massachusetts  business trust (the "Trust"),
adopted  pursuant to the provisions of Rule 12b-1 under the  Investment  Company
Act of 1940  (the  "Act")  and the  related  agreement  between  the  Trust  and
Oppenheimer Funds  Distributor,  Inc., the principal  underwriter of the Trust's
shares (the  "Distributor.")  During the effective  term of this Plan, the Trust
may make payments to  Massachusetts  Mutual Life Insurance  Company,  the Fund's
Administrator  ("MassMutual"),  upon the terms and  conditions  hereinafter  set
forth:

SECTION 1. The Trust will pay service fees to MassMutual  for services  provided
and expenses  incurred by it for purposes of maintaining  or providing  personal
services  to Class A  shareholders  (the  "Servicing  Fee").  The amount of such
payments  and the purposes  for which they are made shall be  determined  by the
Qualified  Trustees  (as  defined  below).  The  Servicing  Fee may be  spent by
MassMutual on account of personal  services  rendered to Class A shareholders of
the Fund  and/or  maintenance  of  Class A  shareholder  accounts.  MassMutual's
Servicing  Fee  expenditures   may  include,   but  shall  not  be  limited  to,
compensation  to, and expenses  (including  telephone and overhead  expenses) of
financial  consultants or other employees of MassMutual,  the Fund's Distributor
or Sub-Distributor,  pension consultants or participating or introducing brokers
and  other  financial   intermediaries   who  assist   investors  in  completing
application forms and selecting  dividend and other account options;  who aid in
the  process  of  purchase  or  redemption  requests  for  Class A shares or the
processing  of dividend  payments  with  respect to Class A shares;  who provide
information periodically to Class A shareholders showing their position in Class
A shares; who prepare, print and deliver prospectuses and shareholder reports to
prospective Class A shareholders;  who oversee compliance with federal and state
laws  pertaining  to the sale of Class A  shares;  who issue  confirmations  for
transactions by Class A shareholders;  who forward  communications from the Fund
to  Class A  shareholders;  who  render  advice  regarding  the  suitability  of
particular investment  opportunities offered by the Fund in light of shareholder
needs;  who provide and  maintain  elective  shareholder  services;  who furnish
shareholder  sub-accounting;  who provide and maintain pre-authorized investment
plans  for  Class  A  shareholders;  who  respond  to  inquiries  from  Class  A
shareholders relating to such services; and/or who provide such similar services
as permitted under applicable statutes, rules or regulations.

Payments  under this  Section 1 of the Plan shall not exceed in any fiscal  year
the annual rate of .25% of the Fund's average daily net assets  attributable  to
Class A shares.  A majority of the Qualified  Trustees may, at any time and from
time to time,  reduce the amount of such payments,  or may suspend the operation
of the Plan for such period or periods of time as they may determine.

SECTION  2. To the  extent  that any  payments  made by the Fund to  MassMutual,
including payment of management and administrative  fees, should be deemed to be
indirect  financing of any activity  primarily intended to result in the sale of
shares  issued by the Fund within the context of Rule 12b-1 under the Act,  then
such payments shall be deemed to be authorized by this Plan.

SECTION 3. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

                                       9


SECTION 4. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 3.

SECTION 5.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 6. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class A shares
of the Fund.

SECTION 7. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any penalty,  by vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class A shares of the Fund, on not
        more than 60 days' written  notice to any other party to the  agreement;
        and

        (b)   that such agreement shall terminate automatically in the event of
        its assignment.

SECTION  8. This Plan may not be  amended  to  increase  materially  the  amount
permitted  pursuant to Sections 1 hereof  without the  approval of a majority of
the outstanding Class A shares of the Fund, and all material  amendments to this
Plan shall be  approved  in the manner  provided  for  approval  of this Plan in
Section 3.

SECTION 9. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 10. A copy of the Agreement and  Declaration of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class A shares of the Fund.


Executed as of this 26th day of November, 1997.

MASSMUTUAL INSTITUTIONAL                MASSACHUSETTS MUTUAL LIFE
FUNDS ON BEHALF OF MASSMUTUAL           INSURANCE COMPANY
VALUE EQUITY FUND


BY:                                    BY:
   --------------------------------       -------------------------------

                                      10


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

            MASSMUTUAL SMALL CAP VALUE EQUITY FUND: CLASS A SHARES
            ------------------------------------------------------

                           SERVICE PLAN AND AGREEMENT


This Plan and Agreement (the "Plan") constitutes the Service Plan of the Class A
shares of the MassMutual  Small Cap Value Equity Fund (the "Fund"),  a series of
the  MassMutual   Institutional  Funds,  a  Massachusetts  business  trust  (the
"Trust"),  adopted pursuant to the provisions of Rule 12b-1 under the Investment
Company Act of 1940 (the "Act") and the related  agreement between the Trust and
Oppenheimer Funds  Distributor,  Inc., the principal  underwriter of the Trust's
shares (the  "Distributor.")  During the effective  term of this Plan, the Trust
may make payments to  Massachusetts  Mutual Life Insurance  Company,  the Fund's
Administrator  ("MassMutual"),  upon the terms and  conditions  hereinafter  set
forth:

SECTION 1. The Trust will pay service fees to MassMutual  for services  provided
and expenses  incurred by it for purposes of maintaining  or providing  personal
services  to Class A  shareholders  (the  "Servicing  Fee").  The amount of such
payments  and the purposes  for which they are made shall be  determined  by the
Qualified  Trustees  (as  defined  below).  The  Servicing  Fee may be  spent by
MassMutual on account of personal  services  rendered to Class A shareholders of
the Fund  and/or  maintenance  of  Class A  shareholder  accounts.  MassMutual's
Servicing  Fee  expenditures   may  include,   but  shall  not  be  limited  to,
compensation  to, and expenses  (including  telephone and overhead  expenses) of
financial  consultants or other employees of MassMutual,  the Fund's Distributor
or Sub-Distributor,  pension consultants or participating or introducing brokers
and  other  financial   intermediaries   who  assist   investors  in  completing
application forms and selecting  dividend and other account options;  who aid in
the  process  of  purchase  or  redemption  requests  for  Class A shares or the
processing  of dividend  payments  with  respect to Class A shares;  who provide
information periodically to Class A shareholders showing their position in Class
A shares; who prepare, print and deliver prospectuses and shareholder reports to
prospective Class A shareholders;  who oversee compliance with federal and state
laws  pertaining  to the sale of Class A  shares;  who issue  confirmations  for
transactions by Class A shareholders;  who forward  communications from the Fund
to  Class A  shareholders;  who  render  advice  regarding  the  suitability  of
particular investment  opportunities offered by the Fund in light of shareholder
needs;  who provide and  maintain  elective  shareholder  services;  who furnish
shareholder  sub-accounting;  who provide and maintain pre-authorized investment
plans  for  Class  A  shareholders;  who  respond  to  inquiries  from  Class  A
shareholders relating to such services; and/or who provide such similar services
as permitted under applicable statutes, rules or regulations.

Payments  under this  Section 1 of the Plan shall not exceed in any fiscal  year
the annual rate of .25% of the Fund's average daily net assets  attributable  to
Class A shares.  A majority of the Qualified  Trustees may, at any time and from
time to time,  reduce the amount of such payments,  or may suspend the operation
of the Plan for such period or periods of time as they may determine.

SECTION  2. To the  extent  that any  payments  made by the Fund to  MassMutual,
including payment of management and administrative  fees, should be deemed to be
indirect  financing of any activity  primarily intended to result in the sale of
shares  issued by the Fund within the context of Rule 12b-1 under the Act,  then
such payments shall be deemed to be authorized by this Plan.

SECTION 3. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

                                      11


SECTION 4. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 3.

SECTION 5.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 6. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class A shares
of the Fund.

SECTION 7. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any penalty,  by vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class A shares of the Fund, on not
        more than 60 days' written  notice to any other party to the  agreement;
        and

        (b)   that such agreement shall terminate automatically in the event of
        its assignment.

SECTION  8. This Plan may not be  amended  to  increase  materially  the  amount
permitted  pursuant to Sections 1 hereof  without the  approval of a majority of
the outstanding Class A shares of the Fund, and all material  amendments to this
Plan shall be  approved  in the manner  provided  for  approval  of this Plan in
Section 3.

SECTION 9. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 10. A copy of the Agreement and  Declaration of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class A shares of the Fund.

Executed as of this 26th day of November, 1997.

MASSMUTUAL INSTITUTIONAL                MASSACHUSETTS MUTUAL LIFE
FUNDS ON BEHALF OF MASSMUTUAL           INSURANCE COMPANY
SMALL CAP VALUE EQUITY FUND


BY:                                     BY:
   --------------------------------        -------------------------------

                                      12


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

             MASSMUTUAL INTERNATIONAL EQUITY FUND: CLASS A SHARES
             ----------------------------------------------------

                           SERVICE PLAN AND AGREEMENT


This Plan and Agreement (the "Plan") constitutes the Service Plan of the Class A
shares of the MassMutual International Equity Fund (the "Fund"), a series of the
MassMutual  Institutional  Funds, a Massachusetts  business trust (the "Trust"),
adopted  pursuant to the provisions of Rule 12b-1 under the  Investment  Company
Act of 1940  (the  "Act")  and the  related  agreement  between  the  Trust  and
Oppenheimer Funds  Distributor,  Inc., the principal  underwriter of the Trust's
shares (the  "Distributor.")  During the effective  term of this Plan, the Trust
may make payments to  Massachusetts  Mutual Life Insurance  Company,  the Fund's
Administrator  ("MassMutual"),  upon the terms and  conditions  hereinafter  set
forth:

SECTION 1. The Trust will pay service fees to MassMutual  for services  provided
and expenses  incurred by it for purposes of maintaining  or providing  personal
services  to Class A  shareholders  (the  "Servicing  Fee").  The amount of such
payments  and the purposes  for which they are made shall be  determined  by the
Qualified  Trustees  (as  defined  below).  The  Servicing  Fee may be  spent by
MassMutual on account of personal  services  rendered to Class A shareholders of
the Fund  and/or  maintenance  of  Class A  shareholder  accounts.  MassMutual's
Servicing  Fee  expenditures   may  include,   but  shall  not  be  limited  to,
compensation  to, and expenses  (including  telephone and overhead  expenses) of
financial  consultants or other employees of MassMutual,  the Fund's Distributor
or Sub-Distributor,  pension consultants or participating or introducing brokers
and  other  financial   intermediaries   who  assist   investors  in  completing
application forms and selecting  dividend and other account options;  who aid in
the  process  of  purchase  or  redemption  requests  for  Class A shares or the
processing  of dividend  payments  with  respect to Class A shares;  who provide
information periodically to Class A shareholders showing their position in Class
A shares; who prepare, print and deliver prospectuses and shareholder reports to
prospective Class A shareholders;  who oversee compliance with federal and state
laws  pertaining  to the sale of Class A  shares;  who issue  confirmations  for
transactions by Class A shareholders;  who forward  communications from the Fund
to  Class A  shareholders;  who  render  advice  regarding  the  suitability  of
particular investment  opportunities offered by the Fund in light of shareholder
needs;  who provide and  maintain  elective  shareholder  services;  who furnish
shareholder  sub-accounting;  who provide and maintain pre-authorized investment
plans  for  Class  A  shareholders;  who  respond  to  inquiries  from  Class  A
shareholders relating to such services; and/or who provide such similar services
as permitted under applicable statutes, rules or regulations.

Payments  under this  Section 1 of the Plan shall not exceed in any fiscal  year
the annual rate of .25% of the Fund's average daily net assets  attributable  to
Class A shares.  A majority of the Qualified  Trustees may, at any time and from
time to time,  reduce the amount of such payments,  or may suspend the operation
of the Plan for such period or periods of time as they may determine.

SECTION  2. To the  extent  that any  payments  made by the Fund to  MassMutual,
including payment of management and administrative  fees, should be deemed to be
indirect  financing of any activity  primarily intended to result in the sale of
shares  issued by the Fund within the context of Rule 12b-1 under the Act,  then
such payments shall be deemed to be authorized by this Plan.

SECTION 3. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

                                      13


SECTION 4. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 3.

SECTION 5.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 6. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class A shares
of the Fund.

SECTION 7. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any penalty,  by vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class A shares of the Fund, on not
        more than 60 days' written  notice to any other party to the  agreement;
        and

       (b)   that such agreement shall terminate automatically in the event of
       its assignment.

SECTION  8. This Plan may not be  amended  to  increase  materially  the  amount
permitted  pursuant to Sections 1 hereof  without the  approval of a majority of
the outstanding Class A shares of the Fund, and all material  amendments to this
Plan shall be  approved  in the manner  provided  for  approval  of this Plan in
Section 3.

SECTION 9. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 10. A copy of the Agreement and  Declaration of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class A shares of the Fund.

Executed as of this 26th day of November, 1997.

MASSMUTUAL INSTITUTIONAL                MASSACHUSETTS MUTUAL LIFE
FUNDS ON BEHALF OF MASSMUTUAL           INSURANCE COMPANY
INTERNATIONAL EQUITY FUND


BY:                                     BY:
   --------------------------------        -------------------------------

                                      14


                                                                    Exhibit 15.B

                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                      MASSMUTUAL PRIME FUND: CLASS Y SHARES
                     -------------------------------------

                  DISTRIBUTION AND SERVICE PLAN AND AGREEMENT


This Plan and Agreement (the "Plan")  constitutes the  Distribution  and Service
Plan of the Class Y shares of the MassMutual  Prime Fund (the "Fund"),  a series
of the  MassMutual  Institutional  Funds,  a  Massachusetts  business trust (the
"Trust"),  adopted pursuant to the provisions of Rule 12b-1 under the Investment
Company Act of 1940 (the "Act") and the related  agreement between the Trust and
Oppenheimer Funds  Distributor,  Inc., the principal  underwriter of the Trust's
shares (the  "Distributor").  During the effective  term of this Plan, the Trust
may make payments to Massachusetts Mutual Life Insurance Company  ("MassMutual")
upon the terms and conditions hereinafter set forth:


SECTION 1. To the extent  that any  payments  made by the Fund to  Massachusetts
Mutual  Life   Insurance   Company,   including   payment  of   management   and
administrative  fees, should be deemed to be indirect  financing of any activity
primarily intended to result in the sale of shares issued by the Fund within the
context of Rule 12b-1 under the Act,  then such  payments  shall be deemed to be
authorized by the Plan.


SECTION 2. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

SECTION 3. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 2.

SECTION 4.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 5. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class Y shares
of the Fund.

SECTION 6. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:


        (a) that such agreement may be terminated at any time,  without  payment
        of any  penalty,by  vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class Y shares of the Fund, on not
        more than 60 days' written notice to any other party to

                                       1


  the agreement;and



  (b) that such agreement shall terminate automatically in the event of its
     assignment.

SECTION  7. This Plan may not be amended to  increase  materially  the amount of
distribution  expenses  permitted  pursuant  to  Sections 1 hereof  without  the
approval of a majority of the  outstanding  Class Y shares of the Fund,  and all
material  amendments  to this Plan shall be approved in the manner  provided for
approval of this Plan in Section 2.

SECTION 8. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 9. A copy of the Agreement and  Declaration  of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class Y shares of the Fund.

Executed as of this 26th day of November, 1997.

MASSMUTUAL INSTITUTIONAL
FUNDS, ON BEHALF OF MASSMUTUAL
PRIME FUND

BY:  _____________________________


MASSACHUSETTS MUTUAL LIFE
INSURANCE COMPANY

BY: _____________________________

                                       2


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                MASSMUTUAL SHORT-TERM BOND FUND: CLASS Y SHARES
                -----------------------------------------------

                  DISTRIBUTION AND SERVICE PLAN AND AGREEMENT

This Plan and Agreement (the "Plan")  constitutes the  Distribution  and Service
Plan of the Class Y shares of the MassMutual  Short-Term Bond Fund (the "Fund"),
a series of the MassMutual  Institutional Funds, a Massachusetts  business trust
(the  "Trust"),  adopted  pursuant  to the  provisions  of Rule 12b-1  under the
Investment Company Act of 1940 (the "Act") and the related agreement between the
Trust and Oppenheimer Funds Distributor,  Inc., the principal underwriter of the
Trust's shares (the "Distributor").  During the effective term of this Plan, the
Trust  may  make  payments  to  Massachusetts   Mutual  Life  Insurance  Company
("MassMutual") upon the terms and conditions hereinafter set forth:


SECTION 1. To the extent  that any  payments  made by the Fund to  Massachusetts
Mutual  Life   Insurance   Company,   including   payment  of   management   and
administrative  fees, should be deemed to be indirect  financing of any activity
primarily intended to result in the sale of shares issued by the Fund within the
context of Rule 12b-1 under the Act,  then such  payments  shall be deemed to be
authorized by the Plan.

SECTION 2. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

SECTION 3. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 2.

SECTION 4.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 5. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class Y shares
of the Fund.

SECTION 6. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any  penalty,by  vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class Y shares of the Fund, on not
        more than 60 days' written notice to any other party to

                                       3


 the agreement;and

 (b) that such agreement shall terminate automatically in the event of its
 assignment.


SECTION  7. This Plan may not be amended to  increase  materially  the amount of
distribution  expenses  permitted  pursuant  to  Sections 1 hereof  without  the
approval of a majority of the  outstanding  Class Y shares of the Fund,  and all
material  amendments  to this Plan shall be approved in the manner  provided for
approval of this Plan in Section 2.

SECTION 8. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 9. A copy of the Agreement and  Declaration  of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class Y shares of the Fund.

Executed as of this 26th day of November, 1997.

MASSMUTUAL INSTITUTIONAL
FUNDS, ON BEHALF OF MASSMUTUAL
SHORT-TERM BOND FUND

BY:  _____________________________

MASSACHUSETTS MUTUAL LIFE
INSURANCE COMPANY

BY: _____________________________

                                       4


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                   MASSMUTUAL CORE BOND FUND: CLASS Y SHARES
                   -----------------------------------------

                  DISTRIBUTION AND SERVICE PLAN AND AGREEMENT

This Plan and Agreement (the "Plan")  constitutes the  Distribution  and Service
Plan of the Class Y shares of the  MassMutual  Core  Bond Fund (the  "Fund"),  a
series of the MassMutual  Institutional  Funds, a  Massachusetts  business trust
(the  "Trust"),  adopted  pursuant  to the  provisions  of Rule 12b-1  under the
Investment Company Act of 1940 (the "Act") and the related agreement between the
Trust and Oppenheimer Funds Distributor,  Inc., the principal underwriter of the
Trust's shares (the "Distributor").  During the effective term of this Plan, the
Trust  may  make  payments  to  Massachusetts   Mutual  Life  Insurance  Company
("MassMutual") upon the terms and conditions hereinafter set forth:

SECTION 1. To the extent  that any  payments  made by the Fund to  Massachusetts
Mutual  Life   Insurance   Company,   including   payment  of   management   and
administrative  fees, should be deemed to be indirect  financing of any activity
primarily intended to result in the sale of shares issued by the Fund within the
context of Rule 12b-1 under the Act,  then such  payments  shall be deemed to be
authorized by the Plan.

SECTION 2. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

SECTION 3. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 2.

SECTION 4.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 5. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class Y shares
of the Fund.

SECTION 6. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any  penalty,by  vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class Y shares of the Fund, on not
        more than 60 days' written notice to any other party to

                                       5


  the agreement; and

  (b) that such agreement shall terminate automatically in the event of its
     assignment.


SECTION  7. This Plan may not be amended to  increase  materially  the amount of
distribution  expenses  permitted  pursuant  to  Sections 1 hereof  without  the
approval of a majority of the  outstanding  Class Y shares of the Fund,  and all
material  amendments  to this Plan shall be approved in the manner  provided for
approval of this Plan in Section 2.

SECTION 8. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 9. A copy of the Agreement and  Declaration  of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class Y shares of the Fund.

Executed as of this 26th day of November, 1997.


MASSMUTUAL INSTITUTIONAL
FUNDS, ON BEHALF OF MASSMUTUAL
CORE BOND FUND

BY:  _____________________________


MASSACHUSETTS MUTUAL LIFE
INSURANCE COMPANY

BY: _____________________________





                                       6


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                   MASSMUTUAL BALANCED FUND: CLASS Y SHARES
                   ----------------------------------------

                  DISTRIBUTION AND SERVICE PLAN AND AGREEMENT

This Plan and Agreement (the "Plan")  constitutes the  Distribution  and Service
Plan of the Class Y shares of the  MassMutual  Balanced  Fund  (the  "Fund"),  a
series of the MassMutual  Institutional  Funds, a  Massachusetts  business trust
(the  "Trust"),  adopted  pursuant  to the  provisions  of Rule 12b-1  under the
Investment Company Act of 1940 (the "Act") and the related agreement between the
Trust and Oppenheimer Funds Distributor,  Inc., the principal underwriter of the
Trust's shares (the "Distributor").  During the effective term of this Plan, the
Trust  may  make  payments  to  Massachusetts   Mutual  Life  Insurance  Company
("MassMutual") upon the terms and conditions hereinafter set forth:

SECTION 1. To the extent  that any  payments  made by the Fund to  Massachusetts
Mutual  Life   Insurance   Company,   including   payment  of   management   and
administrative  fees, should be deemed to be indirect  financing of any activity
primarily intended to result in the sale of shares issued by the Fund within the
context of Rule 12b-1 under the Act,  then such  payments  shall be deemed to be
authorized by the Plan.

SECTION 2. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

SECTION 3. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 2.

SECTION 4.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 5. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class Y shares
of the Fund.

SECTION 6. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any penalty,  by vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class Y shares of the Fund, on not
        more than 60 days' wri tten notice to any other party to

                                       7


  the agreement; and

  (b) that such agreement shall terminate automatically in the event of its
      assignment.

SECTION  7. This Plan may not be amended to  increase  materially  the amount of
distribution  expenses  permitted  pursuant  to  Sections 1 hereof  without  the
approval of a majority of the  outstanding  Class Y shares of the Fund,  and all
material  amendments  to this Plan shall be approved in the manner  provided for
approval of this Plan in Section 2.

SECTION 8. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 9. A copy of the Agreement and  Declaration  of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class Y shares of the Fund.

Executed as of this 26th day of November, 1997.


MASSMUTUAL INSTITUTIONAL
FUNDS, ON BEHALF OF MASSMUTUAL

BALANCED FUND


BY:  _____________________________


MASSACHUSETTS MUTUAL LIFE
INSURANCE COMPANY

BY: _____________________________

                                       8


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                 MASSMUTUAL VALUE EQUITY FUND: CLASS Y SHARES
                 --------------------------------------------

                  DISTRIBUTION AND SERVICE PLAN AND AGREEMENT


This Plan and Agreement (the "Plan")  constitutes the  Distribution  and Service
Plan of the Class Y shares of the MassMutual  Value Equity Fund (the "Fund"),  a
series of the MassMutual  Institutional  Funds, a  Massachusetts  business trust
(the  "Trust"),  adopted  pursuant  to the  provisions  of Rule 12b-1  under the
Investment Company Act of 1940 (the "Act") and the related agreement between the
Trust and Oppenheimer Funds Distributor,  Inc., the principal underwriter of the
Trust's shares (the "Distributor").  During the effective term of this Plan, the
Trust  may  make  payments  to  Massachusetts   Mutual  Life  Insurance  Company
("MassMutual") upon the terms and conditions hereinafter set forth:

SECTION 1. To the extent  that any  payments  made by the Fund to  Massachusetts
Mutual  Life   Insurance   Company,   including   payment  of   management   and
administrative  fees, should be deemed to be indirect  financing of any activity
primarily intended to result in the sale of shares issued by the Fund within the
context of Rule 12b-1 under the Act,  then such  payments  shall be deemed to be
authorized by the Plan.

SECTION 2. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

SECTION 3. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 2.

SECTION 4.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 5. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class Y shares
of the Fund.

SECTION 6. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

(a) that such  agreement may be terminated at any time,  without  payment of any
penalty,by vote of a majority of the Qualified Trustees or by vote of a majority
o the outstanding  Class Y shares of the Fund, on not more than 60 days' written
notice to any other party to

                                       9


     the agreement; and

     (b) that such agreement shall terminate automatically in the event of its
     assignment.

SECTION  7. This Plan may not be amended to  increase  materially  the amount of
distribution  expenses  permitted  pursuant  to  Sections 1 hereof  without  the
approval of a majority of the  outstanding  Class Y shares of the Fund,  and all
material  amendments  to this Plan shall be approved in the manner  provided for
approval of this Plan in Section 2.

SECTION 8. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 9. A copy of the Agreement and  Declaration  of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class Y shares of the Fund.


Executed as of this 26th day of November, 1997.


MASSMUTUAL INSTITUTIONAL
FUNDS, ON BEHALF OF MASSMUTUAL
VALUE EQUITY FUND

BY:  _____________________________


MASSACHUSETTS MUTUAL LIFE
INSURANCE COMPANY

BY: _____________________________





                                       10


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                MASSMUTUAL SMALL CAP VALUE EQUITY FUND: CLASS Y SHARES
                ------------------------------------------------------

                  DISTRIBUTION AND SERVICE PLAN AND AGREEMENT

This Plan and Agreement (the "Plan")  constitutes the  Distribution  and Service
Plan of the Class Y shares of the  MassMutual  Small Cap Value  Equity Fund (the
"Fund"),  a  series  of the  MassMutual  Institutional  Funds,  a  Massachusetts
business trust (the "Trust"),  adopted  pursuant to the provisions of Rule 12b-1
under the Investment  Company Act of 1940 (the "Act") and the related  agreement
between  the  Trust and  Oppenheimer  Funds  Distributor,  Inc.,  the  principal
underwriter of the Trust's shares (the "Distributor"). During the effective term
of this Plan, the Trust may make payments to Massachusetts Mutual Life Insurance
Company ("MassMutual") upon the terms and conditions hereinafter set forth:

SECTION 1. To the extent  that any  payments  made by the Fund to  Massachusetts
Mutual  Life   Insurance   Company,   including   payment  of   management   and
administrative  fees, should be deemed to be indirect  financing of any activity
primarily intended to result in the sale of shares issued by the Fund within the
context of Rule 12b-1 under the Act,  then such  payments  shall be deemed to be
authorized by the Plan.

SECTION 2. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

SECTION 3. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 2.

SECTION 4.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 5. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class Y shares
of the Fund.

SECTION 6. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:


        (a) that such agreement may be terminated at any time,  without  payment
        of any  penalty,by  vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class Y shares of the Fund, on not
        more than 60 days' written notice to any other party to

                                       11


  the agreement; and

  (b) that such agreement shall terminate automatically in the event of its
      assignment.

SECTION  7. This Plan may not be amended to  increase  materially  the amount of
distribution  expenses  permitted  pursuant  to  Sections 1 hereof  without  the
approval of a majority of the  outstanding  Class Y shares of the Fund,  and all
material  amendments  to this Plan shall be approved in the manner  provided for
approval of this Plan in Section 2.

SECTION 8. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 9. A copy of the Agreement and  Declaration  of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class Y shares of the Fund.

Executed as of this 26th day of November, 1997.


MASSMUTUAL INSTITUTIONAL
FUNDS, ON BEHALF OF MASSMUTUAL
SMALL CAP VALUE EQUITY FUND

BY:  _____________________________


MASSACHUSETTS MUTUAL LIFE
INSURANCE COMPANY

BY: _____________________________





                                       12


                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                 MASSMUTUAL INTERNATIONAL EQUITY FUND: CLASS Y SHARES
                 ----------------------------------------------------

                  DISTRIBUTION AND SERVICE PLAN AND AGREEMENT

This Plan and Agreement (the "Plan")  constitutes the  Distribution  and Service
Plan of the  Class Y shares of the  MassMutual  International  Equity  Fund (the
"Fund"),  a  series  of the  MassMutual  Institutional  Funds,  a  Massachusetts
business trust (the "Trust"),  adopted  pursuant to the provisions of Rule 12b-1
under the Investment  Company Act of 1940 (the "Act") and the related  agreement
between  the  Trust and  Oppenheimer  Funds  Distributor,  Inc.,  the  principal
underwriter of the Trust's shares (the "Distributor"). During the effective term
of this Plan, the Trust may make payments to Massachusetts Mutual Life Insurance
Company ("MassMutual") upon the terms and conditions hereinafter set forth:


SECTION 1. To the extent  that any  payments  made by the Fund to  Massachusetts
Mutual  Life   Insurance   Company,   including   payment  of   management   and
administrative  fees, should be deemed to be indirect  financing of any activity
primarily intended to result in the sale of shares issued by the Fund within the
context of Rule 12b-1 under the Act,  then such  payments  shall be deemed to be
authorized by the Plan.

SECTION 2. This Plan shall not take effect until it has been approved,  together
with any related  agreements,  by votes of the  majority  (or  whatever  greater
percentage  may,  from time to time,  be required by Section 12(b) of the Act or
the rules and regulations thereunder) of both (i) the Trustees of the Trust, and
(ii) the Qualified Trustees of the Trust, cast in person at a meeting called for
the purpose of voting on this Plan or such agreement.

SECTION 3. This Plan shall continue in effect for a period of more than one year
after it takes effect only so long as such continuance is specifically  approved
at least annually in the manner provided for approval of this Plan in Section 2.

SECTION 4.  MassMutual  shall  provide  to the  Trustees  of the Trust,  and the
Trustees shall review,  at least  quarterly,  a written report of the amounts so
expended and the purposes for which such expenditures were made.

SECTION 5. This Plan may be  terminated at any time by vote of a majority of the
Qualified  Trustees,  or by vote of a majority of the outstanding Class Y shares
of the Fund.

SECTION 6. All agreements  with any person  relating to  implementation  of this
Plan shall be in writing, and any agreement related to this Plan shall provide:

        (a) that such agreement may be terminated at any time,  without  payment
        of any  penalty,by  vote of a majority of the  Qualified  Trustees or by
        vote of a majority of the outstanding Class Y shares of the Fund, on not
        more than 60 days' written notice to any other party to

                                       13


  the agreement; and

  (b) that such agreement shall terminate automatically in the event of its
      assignment.


SECTION  7. This Plan may not be amended to  increase  materially  the amount of
distribution  expenses  permitted  pursuant  to  Sections 1 hereof  without  the
approval of a majority of the  outstanding  Class Y shares of the Fund,  and all
material  amendments  to this Plan shall be approved in the manner  provided for
approval of this Plan in Section 2.


SECTION 8. As used in this Plan, (a) the term  "Qualified  Trustees"  shall mean
those  Trustees of the Trust who are not  interested  persons of the Trust,  and
have no direct or indirect  financial  interest in the operation of this Plan or
any agreements related to it, and (b) the terms "interested person" and "vote of
a majority  of the  outstanding  voting  securities"  shall have the  respective
meanings specified in the Act and the rules and regulations thereunder,  subject
to such exemptions as may be granted by the Securities and Exchange Commission.

SECTION 9. A copy of the Agreement and  Declaration  of Trust of the Trust is on
file with the Secretary of State of The Commonwealth of Massachusetts and notice
is hereby  given that this  instrument  is executed on behalf of the Trustees of
the Trust as  Trustees  and not  individually,  and that the  obligations  of or
arising  out of  this  instrument  are not  binding  upon  any of the  Trustees,
officers or shareholders  individually  but are binding only upon the assets and
property attributable to the Class Y shares of the Fund.

Executed as of this 26th day of November, 1997.

MASSMUTUAL INSTITUTIONAL
FUNDS, ON BEHALF OF MASSMUTUAL
INTERNATIONAL EQUITY FUND

BY:  _____________________________

MASSACHUSETTS MUTUAL LIFE
INSURANCE COMPANY

BY: _____________________________





                                       14


                                                                      EXHIBIT 18

                                     FORM OF
                                    -------

                         MASSMUTUAL INSTITUTIONAL FUNDS
                        ------------------------------

                              AMENDED AND RESTATED
                             --------------------

                                 RULE 18F-3 PLAN
                                ---------------

                             Adopted August 4, 1997

                                  Introduction


MassMutual  Institutional Funds (the "Trust") is a Massachusetts  business trust
registered  under  the  Investment  Company  Act of 1940 (the  "1940  Act") as a
diversified,  open-end management investment company.  Massachusetts Mutual Life
Insurance  Company (the "Adviser") is a mutual life insurance  company organized
under Massachusetts law. OppenheimerFunds  Distributor, Inc. (the "Distributor")
is a  registered  broker-dealer  which serves as  principal  underwriter  to the
Trust.  The Trust consists of seven separate series and expects to add up to six
(6) additional  series (the  "Funds"),  each of which has and will have separate
investment  objectives.  Prior to the adoption of this Amended and Restated Rule
18f-3 Plan, each Fund had four (4) classes of shares - Class 1, Class 2, Class 3
and Class 4. With the  adoption of this  Amended and  Restated  Rule 18f-3 Plan,
each Fund will have  three (3)  classes of shares - Class A, Class Y and Class 4
(redesignated and referred to now as Class S).

This plan is prepared,  and is being adopted by the Board of Trustees,  pursuant
to the requirements of Rule 18f-3 (the "Rule 18f-3 Plan").

                             Description of Classes

Class A. Class A shares are marketed primarily to defined contribution plans and
defined benefit plans that qualify under section 401(a) of the Internal  Revenue
Code of 1986, as amended (the "Code"),  individual retirement accounts described
in Code section 408, and tax-sheltered  annuity custodial  accounts described in
Code  section  403(b)(7).   Class  A  shares  may  also  be  marketed  to  other
institutional  investors such as deferred  compensation  plans described in Code
section 457, voluntary  employees'  beneficiary  associations  described in Code
section  501(c)(9),  other  non-qualified  deferred  compensation plans or other
institutional or sophisticated investors.  Class A shares may also be offered to
present  or former  officers,  directors,  trustees  and  employees  (and  their
spouses,  parents,  children  and  siblings)  of the Trust,  the Adviser and its
affiliates and retirement plans established by them for their employees. Class A
shares may be offered with a front-end  sales charge,  as described from time to
time, in the Porspectus and/or Statement of Additional  Information  included in
the Trust's Registration  Statement, as amended from time to time, provided that
such  front-end  sales charge shall not exceed 5.75%.  In cases where  front-end
sales charges are not imposed and Class A shares are offered at net asset value,
there may be contingent deferred sales charges applied for redemptions occurring
in the 12 month period occurring after the first purchase.

Class  Y.  Class Y shares  are  marketed  primarily  to  non-qualified  deferred
compensation  plans whereby the employer  sponsor enters into an  administrative
services  agreement  with the Adviser,  or an  affiliate  of the  Adviser,  with
respect to  administration  of the plan.  Class Y shares may also be marketed to
defined  contribution  plans and defined benefit plans under Code section 401(a)
and  tax-sheltered  annuity plans under Code Section  403(b),  in each case with
plan  assets  in  excess  of  a  determined  amount  and  which  enter  into  an
administrative  services or other agreement with the Adviser, or an affiliate of
the  Adviser.  Class Y  shares  may  also be  marketed  to  other  institutional
investors,  including  other  registered  investment  Companies  (or any  series
thereof)  advised by the Adviser or an affiliate of the Adviser.  Class Y shares
will be offered at net asset value  without a front-end or  contingent  deferred
sales charge.

                                                                          Page 1


Class S. Class S shares  are  available  only to the  separate  accounts  of the
Adviser  and  life  insurance  company  affiliates  of  the  Adviser  ("Separate
Accounts").  Interests  in the  Separate  Accounts  are offered  only to defined
contribution  plans and  defined  benefit  plans under Code  section  401(a) and
certain other plans in accordance with the Federal securities laws and the rules
and  regulations  thereunder.  Class S shares  are  offered  at net asset  value
without a front-end or contingent  deferred  sales  charge.  Class S shares were
formerly known as Class 4 shares.

                             Servicing Arrangements

Class A. It is  anticipated  that Class A shares will primarily be marketed both
through  independent  and  affiliated  broker/dealers  with  the  assistance  of
independent  intermediaries,  but Class A shares  also may be sold  directly  by
employees of the Adviser. In addition, there may also be "direct" sales of Class
A shares by  employees  of the  Adviser in the case of Class A shares  which are
sold to participants of qualified plans who roll their plan  distributions  into
individual  retirement  accounts.  In either case, such employees of the Adviser
shall be registered representatives of a broker-dealer affiliate of the Adviser.

Class Y. It is  anticipated  that  Class Y  shares  will be  marketed  primarily
through "direct" sales efforts of employees of the Adviser,  but that there will
also be sales by field representatives of the Adviser. In either case, employees
of the Adviser shall be registered  representatives of a broker-dealer affiliate
of the  Adviser.  Class Y shares may also be marketed  through  independent  and
affiliated broker/dealers with the assistance of independent intermediaries.

Class S. Class S shares may be sold only to Separate Accounts. It is anticipated
that there will not be any "direct"  sales of Class S shares by employees of the
Adviser  and  sales  of  Separate  Accounts  need  not  be  made  by  registered
representatives.

                         Servicing Arrangements -- Fees

In General. Each Fund has adopted or will adopt with respect to Class A shares a
Service Plan and Agreement pursuant to Rule 12b-1 under the 1940 Act (a "Service
Plan")  which will  provide  for  payment of service  fees to the  Adviser  (the
"Service  Fee") for the rendering of personal  services to Class A  shareholders
and/or maintenance of Class A shareholder accounts. The Adviser will not use the
Service  Fee  charged  to  Class A within a Fund to  support  the  distribution,
marketing  or  shareholder  services  of any other  class  within  the  Fund.  A
defensive Rule 12b-1 Plan has been adopted for Class A and Class Y.

Class A. The Class A Service Plan  provides that the Service Fee will be paid to
the Adviser at an annual rate not to exceed .25% of the average  daily net asset
value of the Class A shares.

                                                                          Page 2


Class Y. Class Y shares are not subject to any service fees,  although the Class
does have a defensive 12b-1 Plan. Any expenses related to sales and distribution
would be borne by the Adviser and not by the Trust.

Class S. Class S shares are not subject to Rule 12b-1 fees because there are not
expected to be any distribution or service expenses  attributable to Class S due
to the nature of the investors eligible to purchase Class S shares.

                           Administrative Arrangements

The Adviser has entered into a separate  Administrative and Shareholder Services
Agreement  for each  Fund  pursuant  to which the  Adviser  is  compensated  for
administrative and shareholder  services rendered and expenses incurred by it in
the rendering of such services and for the cost of bearing some Class  expenses,
such as  Federal  and  state  registration  fees,  printing  and  postage.  Each
Agreement  anticipates that the Adviser will provide extensive services to Class
A, modest  services to Class Y and  limited  services to Class S. The Trust,  on
behalf of each Fund,  pays the Adviser a monthly fee for the services  performed
at an annual rate of the  average  daily net assets of the  applicable  class of
shares of the Fund within the range specified below. The administrative services
fee is an Identifiable Class Expense.

Also, as described  above in the section  entitled  Distribution  Arrangement --
Fees,  Class A shares  will bear a service fee which is used to  compensate  the
Adviser  for  rendering  personal  services  to  shareholders  and for  expenses
incurred by it in the rendering of such services.

                       Administrative Arrangements -- Fees

Each Class of each Fund shall  bear an  administrative  fee as set forth in each
Fund's  Administrative and Shareholder  Services Agreement.  Such fees will vary
from Class to Class and may vary from Fund to Fund. Set forth below is the range
of  administrative  fees paid by each  Class of the  existing  seven  funds (the
MassMutual  Prime Fund,  MassMutual  Short-Term Bond Fund,  MassMutual  Balanced
Fund,  MassMutual Value Equity Fund,  MassMutual Small Cap Value Equity Fund and
MassMutual International Equity Fund).

Class A. Class A shares  will bear an annual  administrative  service fee not to
exceed a range of between .56% and .59%.

Class Y. Class Y shares  will bear an annual  administrative  service fee not to
exceed a range of between .31% and .44%.

Class S. Class S shares  will bear an annual  administrative  service fee not to
exceed a range of between .08% and .10%.

                     Voting and Other Rights and Obligations

Each  share of the  Trust,  regardless  of class,  will have  identical  voting,
dividend,  liquidation  and other  rights,  preferences,  powers,  restrictions,
limitations, qualifications, designations and terms and conditions, except that:

     (a)  each class will have a different class designation;

     (b)  each class offered in connection  with a Rule 12b-1 Plan will bear the
          expense of the payments that would be made pursuant to such Rule 12b-1
          Plan;

     (c)  each class will also bear  certain  other  expenses  that are directly
          attributable only to the class (the  "Identifiable  Class Expenses" as
          described  in  more  detail  under   "Allocation   of  Fund   Expenses
          Identifiable Class Expenses); and

                                                                          Page 3


        (d) only the  holders of the shares of the  appropriate  class  involved
        will be  entitled  to vote on  matters  pertaining  to a Rule 12b-1 Plan
        relating to such class (e.g., the adoption,  amendment or termination of
        a Rule 12b-1 Plan) in accordance  with the  requirements  and procedures
        set forth in Rule 12b-1;

        (e) each class will have separate voting rights on any matter  submitted
        to  shareholders  in which the  interest of one class  differs  from the
        interest of any other class; and

        (f)  each class will have different exchange privileges described
        below.

Dividends paid by a Fund with respect to each class of shares, to the extent any
dividends are paid, will be calculated in the same manner,  at the same time, on
the same day and will be in the same amount, except that fee payments made under
the Rule 12b-1  Plans  relating  to a  particular  class of shares will be borne
exclusively by such class and except that any Identifiable Class Expenses may be
borne by the applicable class of shares.

                           Allocation of Fund Expenses

Unattributed  Expenses.  All  expenses  of the Trust that  cannot be  attributed
directly to any one Fund will be  allocated  to each Fund based on the  relative
net assets of such Fund. All expenses of a Fund that can not be allocated to any
one  particular  Class will be allocated to each Class based on the relative net
asset of such Class. An independent  expert previously  reviewed the methodology
and  procedures  for the proper  allocation of expenses  among Class 1, Class 2,
Class 3 and Class 4 shares and the expert  rendered a report  that  demonstrated
that  such  methodology  and  procedures  were  adequate  to  ensure  that  such
allocations will be made in an appropriate manner, subject to the conditions and
limitations  in the report (a copy of which is attached).  The  methodology  and
procedures  for the proper  allocation  of  expenses  among Class A, Class Y and
Class S shares will be the same as those reviewed by the independent  expert for
the Class 1, Class 2, Class 3 and Class 4 shares.

Identifiable Class Expenses. Identifiable Class Expenses will be allocated to a
particular class of a Fund and are limited to:

     (a)  transfer agency fees attributable to a specific class of shares;

     (b)  printing and postage  expenses  related to preparing and  distributing
          materials such as  shareholder  reports,  prospectuses  and proxies to
          current shareholders of a specific class;

     (c)  Blue Sky registration fees incurred by a class of shares;

     (d)  SEC registration fees incurred by a class of shares;

     (e)  shareholder and administrative service fees payable under each Fund's
          respective administrative service agreement; and

     (f)  any other incremental expenses subsequently  identified that should be
          properly  allocated  to one class which shall be approved by the Board
          and is consistent with Rule 18f-3 and any SEC interpretations thereof.


                                                                          Page 4


                     Waivers and Reimbursements of Expenses

The Adviser may choose to reimburse or waive the Identifiable  Class Expenses of
certain  classes on a voluntary,  temporary  basis.  The amount of such expenses
waived or reimbursed  by the Adviser may vary from class to class.  In addition,
the Adviser may waive or reimburse expenses  attributable to the Trust generally
and/or   expenses   attributable  to  a  Fund  (with  or  without  a  waiver  or
reimbursement of Identifiable Class Expenses) but only if the same proportionate
amount of such  expenses  are waived or  reimbursed  for each class.  Thus,  any
expenses attributable to the Trust generally that are waived or reimbursed would
be  credited  to each  class of a Fund based on the  relative  net assets of the
classes.  Similarly,  any  expenses  attributable  to a Fund that are  waived or
reimbursed  would be  credited  to each  class  of that  Fund  according  to the
relative net assets of the classes.  The Adviser's  flexibilty to waive expenses
may be subject to tax considerations.

                             No Conversion Provision

In General. Class A, Class Y and Class S shares of the Funds do not have a
conversion feature.

                               Exchange Provision

Class A.  Shareholders of Class A shares of each Fund will generally be entitled
to  exchange  those  shares at net asset value for Class A shares of other Funds
that offer Class A shares. Shareholders of Class A shares continue to be subject
to the Rule 12b-1 Plan fee applicable to Class A shares after the exchange.

Class Y.  Shareholders of Class Y shares of each Fund will generally be entitled
to  exchange  those  shares at net asset value for Class Y shares of other Funds
that offer Class Y shares.

Class S.  Shareholders of Class S shares of each Fund will generally be entitled
to  exchange  those  shares at net asset value for Class S shares of other Funds
that offer Class S shares.

                                 Effective Date

This Amended and Restated Rule 18f-3 Plan shall become  effective upon the first
issuance of Class A and Class Y shares.


Approved:                                       Date:
         ----------------------------------           ---------------------
Title:   Vice President and Secretary



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