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<PAGE> PAGE 10
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<PAGE> PAGE 15
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<PAGE> PAGE 21
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SIGNATURE STEPHEN L. KUHN
TITLE SECRETARY
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
ANNUAL REPORT TO SHAREHOLDERS OF MML SERIES INVESTMENT FUND FOR THE YEAR
ENDED DECEMBER 31, 1996 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT FUND
<SERIES>
<NUMBER> 1
<NAME> MML EQUITY FUND
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1996
<PERIOD-START> JAN-01-1996
<PERIOD-END> DEC-31-1996
<INVESTMENTS-AT-COST> 1,202,821,395
<INVESTMENTS-AT-VALUE> 1,777,728,723
<RECEIVABLES> 5,578,504
<ASSETS-OTHER> 1,849
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,783,309,076
<PAYABLE-FOR-SECURITIES> 356,569
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 80,954,138
<TOTAL-LIABILITIES> 81,310,707
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,126,515,524
<SHARES-COMMON-STOCK> 57,140,244
<SHARES-COMMON-PRIOR> 48,175,574
<ACCUMULATED-NII-CURRENT> 15,927
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (11,812)
<ACCUM-APPREC-OR-DEPREC> 574,907,328
<NET-ASSETS> 1,701,998,369
<DIVIDEND-INCOME> 37,210,441
<INTEREST-INCOME> 8,806,524
<OTHER-INCOME> 0
<EXPENSES-NET> 5,842,999
<NET-INVESTMENT-INCOME> 40,173,966
<REALIZED-GAINS-CURRENT> 39,133,328
<APPREC-INCREASE-CURRENT> 204,554,604
<NET-CHANGE-FROM-OPS> 283,861,898
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 40,161,778
<DISTRIBUTIONS-OF-GAINS> 39,133,368
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 10,091,590
<NUMBER-OF-SHARES-REDEEMED> 2,955,578
<SHARES-REINVESTED> 1,828,658
<NET-CHANGE-IN-ASSETS> 453,099,363
<ACCUMULATED-NII-PRIOR> 3,739
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (11,812)
<GROSS-ADVISORY-FEES> 5,787,673
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 5,842,999
<AVERAGE-NET-ASSETS> 1,517,714,207
<PER-SHARE-NAV-BEGIN> 25.924
<PER-SHARE-NII> 0.703
<PER-SHARE-GAIN-APPREC> 4.547
<PER-SHARE-DIVIDEND> 0.703
<PER-SHARE-DISTRIBUTIONS> 0.685
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 29.786
<EXPENSE-RATIO> 0.38
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
ANNUAL REPORT TO SHAREHOLDERS OF MML SERIES INVESTMENT FUND FOR THE YEAR
ENDED DECEMBER 31, 1996 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT FUND
<SERIES>
<NUMBER> 2
<NAME> MML MONEY MARKET FUND
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1996
<PERIOD-START> JAN-01-1996
<PERIOD-END> DEC-31-1996
<INVESTMENTS-AT-COST> 145,993,740
<INVESTMENTS-AT-VALUE> 145,993,740
<RECEIVABLES> 0
<ASSETS-OTHER> 5,531
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 145,999,271
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 768,229
<TOTAL-LIABILITIES> 768,229
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 143,778,731
<SHARES-COMMON-STOCK> 145,231,042
<SHARES-COMMON-PRIOR> 108,920,201
<ACCUMULATED-NII-CURRENT> 9,702
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (9,702)
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 145,231,042
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 6,814,072
<OTHER-INCOME> 0
<EXPENSES-NET> 654,464
<NET-INVESTMENT-INCOME> 6,159,608
<REALIZED-GAINS-CURRENT> 32
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 6,159,640
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 6,159,640
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 124,468,969
<NUMBER-OF-SHARES-REDEEMED> 94,198,432
<SHARES-REINVESTED> 6,040,304
<NET-CHANGE-IN-ASSETS> 36,310,841
<ACCUMULATED-NII-PRIOR> 9,734
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 612,946
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 654,464
<AVERAGE-NET-ASSETS> 125,100,979
<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> 0.049
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> 0.049
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.52
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
ANNUAL REPORT TO SHAREHOLDERS OF MML SERIES INVESTMENT FUND FOR THE YEAR
ENDED DECEMBER 31, 1996 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS
</LEGEND>
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT FUND
<SERIES>
<NUMBER> 3
<NAME> MML MANAGED BOND FUND
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1996
<PERIOD-START> JAN-01-1996
<PERIOD-END> DEC-31-1996
<INVESTMENTS-AT-COST> 180,627,024
<INVESTMENTS-AT-VALUE> 182,392,642
<RECEIVABLES> 2,287,822
<ASSETS-OTHER> 1,389
<OTHER-ITEMS-ASSETS> 1,177
<TOTAL-ASSETS> 184,683,030
<PAYABLE-FOR-SECURITIES> 1,400
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 3,109,345
<TOTAL-LIABILITIES> 3,110,745
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 180,809,583
<SHARES-COMMON-STOCK> 15,070,294
<SHARES-COMMON-PRIOR> 12,748,690
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> (64,100)
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (1,089,519)
<ACCUM-APPREC-OR-DEPREC> 1,765,618
<NET-ASSETS> 181,572,285
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 12,067,185
<OTHER-INCOME> 0
<EXPENSES-NET> 867,327
<NET-INVESTMENT-INCOME> 11,199,858
<REALIZED-GAINS-CURRENT> (404,955)
<APPREC-INCREASE-CURRENT> (4,664,274)
<NET-CHANGE-FROM-OPS> 6,130,629
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 11,099,070
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 2,922,396
<NUMBER-OF-SHARES-REDEEMED> 1,491,952
<SHARES-REINVESTED> 891,160
<NET-CHANGE-IN-ASSETS> 22,874,147
<ACCUMULATED-NII-PRIOR> 72,567
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 776,885
<GROSS-ADVISORY-FEES> 820,434
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 867,327
<AVERAGE-NET-ASSETS> 171,146,972
<PER-SHARE-NAV-BEGIN> 12.448
<PER-SHARE-NII> 0.776
<PER-SHARE-GAIN-APPREC> (0.401)
<PER-SHARE-DIVIDEND> 0.775
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 12.048
<EXPENSE-RATIO> 0.51
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THE SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
ANNUAL REPORT TO SHAREHOLDERS OF MML SERIES INVESTMENT FUND FOR THE YEAR
ENDED DECEMBER 31, 1996 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT FUND
<SERIES>
<NUMBER> 4
<NAME> MML BLEND FUND
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1996
<PERIOD-START> JAN-01-1996
<PERIOD-END> DEC-31-1996
<INVESTMENTS-AT-COST> 1,626,837,807
<INVESTMENTS-AT-VALUE> 2,158,417,381
<RECEIVABLES> 9,394,377
<ASSETS-OTHER> 1,177
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 2,167,812,935
<PAYABLE-FOR-SECURITIES> 255,381
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 73,567,314
<TOTAL-LIABILITIES> 73,822,695
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,561,810,884
<SHARES-COMMON-STOCK> 95,296,912
<SHARES-COMMON-PRIOR> 88,851,472
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> (870)
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (345,972)
<ACCUM-APPREC-OR-DEPREC> 531,573,229
<NET-ASSETS> 2,093,990,240
<DIVIDEND-INCOME> 30,120,486
<INTEREST-INCOME> 55,389,729
<OTHER-INCOME> 0
<EXPENSES-NET> 7,578,045
<NET-INVESTMENT-INCOME> 77,932,170
<REALIZED-GAINS-CURRENT> 51,283,628
<APPREC-INCREASE-CURRENT> 137,449,802
<NET-CHANGE-FROM-OPS> 266,665,600
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 77,800,925
<DISTRIBUTIONS-OF-GAINS> 51,065,539
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 7,200,298
<NUMBER-OF-SHARES-REDEEMED> 6,061,613
<SHARES-REINVESTED> 5,306,755
<NET-CHANGE-IN-ASSETS> 270,849,310
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (7,094)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (689,082)
<GROSS-ADVISORY-FEES> 7,525,674
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 7,578,045
<AVERAGE-NET-ASSETS> 2,015,536,845
<PER-SHARE-NAV-BEGIN> 20.519
<PER-SHARE-NII> 0.824
<PER-SHARE-GAIN-APPREC> 1.990
<PER-SHARE-DIVIDEND> 0.824
<PER-SHARE-DISTRIBUTIONS> 0.536
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 21.973
<EXPENSE-RATIO> 0.38
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
