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SIGNATURE STEPHEN L. KUHN
TITLE SECRETARY
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT
<SERIES>
<NUMBER> 1
<NAME> MML EQUITY FUND
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1994
<PERIOD-END> DEC-31-1994
<INVESTMENTS-AT-COST> 727,488,157
<INVESTMENTS-AT-VALUE> 860,281,445
<RECEIVABLES> 2,472,377
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<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 687,655,542
<SHARES-COMMON-STOCK> 399,990
<SHARES-COMMON-PRIOR> 323,301
<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 7,705
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (56,602)
<ACCUM-APPREC-OR-DEPREC> 132,793,288
<NET-ASSETS> 820,783,018
<DIVIDEND-INCOME> 23,275,159
<INTEREST-INCOME> 3,814,234
<OTHER-INCOME> 0
<EXPENSES-NET> 3,345,900
<NET-INVESTMENT-INCOME> 23,743,493
<REALIZED-GAINS-CURRENT> 9,479,860
<APPREC-INCREASE-CURRENT> (1,773,621)
<NET-CHANGE-FROM-OPS> 31,449,732
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 23,735,788
<DISTRIBUTIONS-OF-GAINS> 9,536,463
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<NUMBER-OF-SHARES-SOLD> 7,668,310
<NUMBER-OF-SHARES-REDEEMED> 1,955,939
<SHARES-REINVESTED> 1,956,594
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT FUND
<SERIES>
<NUMBER> 2
<NAME> MML MONEY MARKET FUND
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1994
<PERIOD-END> DEC-31-1994
<INVESTMENTS-AT-COST> 92,310,306
<INVESTMENTS-AT-VALUE> 92,310,306
<RECEIVABLES> 2,099
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<TOTAL-ASSETS> 92,315,474
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<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (5,364)
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 91,786,033
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<INTEREST-INCOME> 3,597,807
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<NET-INVESTMENT-INCOME> 3,147,135
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<NET-CHANGE-IN-ASSETS> 18,127,025
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<PER-SHARE-NAV-BEGIN> 1.000
<PER-SHARE-NII> .038
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT FUND
<SERIES>
<NUMBER> 3
<NAME> MML MANAGED BOND INVESTMENT COMPANY
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1994
<PERIOD-END> DEC-31-1994
<INVESTMENTS-AT-COST> 128,690,451
<INVESTMENTS-AT-VALUE> 121,578,046
<RECEIVABLES> 2,101,082
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<ACCUMULATED-NII-CURRENT> 3,286
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<NET-INVESTMENT-INCOME> 8,506,956
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<APPREC-INCREASE-CURRENT> (11,386,882)
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<DISTRIBUTIONS-OF-INCOME> 8,503,670
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<NUMBER-OF-SHARES-SOLD> 1,691,878
<NUMBER-OF-SHARES-REDEEMED> 2,151,153
<SHARES-REINVESTED> 930,847
<NET-CHANGE-IN-ASSETS> (7,899,546)
<ACCUMULATED-NII-PRIOR> 0
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<OVERDISTRIB-NII-PRIOR> (6,556)
<OVERDIST-NET-GAINS-PRIOR> (13,632)
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<GROSS-EXPENSE> 660,636
<AVERAGE-NET-ASSETS> 127,073,191
<PER-SHARE-NAV-BEGIN> 12.405
<PER-SHARE-NII> .792
<PER-SHARE-GAIN-APPREC> (1.264)
<PER-SHARE-DIVIDEND> .792
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<PER-SHARE-NAV-END> 11.141
<EXPENSE-RATIO> .52
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<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT FUND
<SERIES>
<NUMBER> 4
<NAME> MML BLEND FUND
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> DEC-31-1994
<PERIOD-END> DEC-31-1994
<INVESTMENTS-AT-COST> 1,335,589,579
<INVESTMENTS-AT-VALUE> 1,487,300,871
<RECEIVABLES> 7,549,772
<ASSETS-OTHER> 10,933
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<SHARES-COMMON-PRIOR> 708,288
<ACCUMULATED-NII-CURRENT> (496)
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<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (752,204)
<ACCUM-APPREC-OR-DEPREC> 150,519,836
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<PER-SHARE-GAIN-APPREC> (.271)
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</TABLE>
