<PAGE> PAGE 1
000 A000000 08/31/99
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<PAGE> PAGE 2
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010 A000801 MASSACHUSETTS MUTUAL LIFE INSURANCE COMPANY
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010 C030801 01111
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010 A000802 INVESTORS BANK & TRUST COMPANY (SUBADM)
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<PAGE> PAGE 3
013 B010801 BOSTON
013 B020801 MA
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014 A000801 MML INVESTORS SERVICES, INC.
014 B000801 8-27250
014 A000802 OPPENHEIMERFUNDS DISTRIBUTOR, INC.
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014 A000803 CENTENNIAL ASSET MANAGEMENT CORPORATION
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014 A000805 BABSON SECURITIES, CORP.
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<PAGE> PAGE 4
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<PAGE> PAGE 5
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<PAGE> PAGE 6
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<PAGE> PAGE 7
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SIGNATURE
TITLE
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds
form N-SAR for the period ended August 31, 1999
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
<NUMBER> 31
<NAME> Indexed Equity Fund, Class A
<S> <C>
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<PERIOD-END> AUG-31-1999
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<ACCUMULATED-NII-PRIOR> 631,540
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds
form N-SAR for the period ended August 31, 1999
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
<NUMBER> 32
<NAME> Indexed Equity Fund, Class L
<S> <C>
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</TABLE>
<TABLE> <S> <C>
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<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds
form N-SAR for the period ended August 31, 1999
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
<NUMBER> 33
<NAME> Indexed Equity Fund, Class Y
<S> <C>
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<PERIOD-END> AUG-31-1999
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
This schedule contains summary financial information
extracted from The MassMutual Institutional Funds
form N-SAR for the period ended August 31, 1999
and is qualified in its entirety by reference to
such financial statements.
</LEGEND>
<SERIES>
<NUMBER> 34
<NAME> Indexed Equity Fund, Class S
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> FEB-29-2000
<PERIOD-END> AUG-31-1999
<INVESTMENTS-AT-COST> 0
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</TABLE>
