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<PAGE> PAGE 11
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075 A000400 0
075 B000400 1586982
076 000400 0.00
SIGNATURE STEPHEN L. KUHN
TITLE SECRETARY
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT FUND
<SERIES>
<NUMBER> 1
<NAME> MML EQUITY FUND
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1995
<PERIOD-END> JUN-30-1995
<INVESTMENTS-AT-COST> 813,433,683
<INVESTMENTS-AT-VALUE> 1,060,019,819
<RECEIVABLES> 2,206,505
<ASSETS-OTHER> 255,225
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,062,481,549
<PAYABLE-FOR-SECURITIES> 1,568,838
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 1,047,281
<TOTAL-LIABILITIES> 2,616,119
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 785,196,294
<SHARES-COMMON-STOCK> 44,503,554
<SHARES-COMMON-PRIOR> 39,999,028
<ACCUMULATED-NII-CURRENT> 13,813,063
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 13,824,901
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 246,586,136
<NET-ASSETS> 1,059,865,430
<DIVIDEND-INCOME> 12,942,852
<INTEREST-INCOME> 2,858,606
<OTHER-INCOME> 0
<EXPENSES-NET> 1,944,195
<NET-INVESTMENT-INCOME> 13,857,263
<REALIZED-GAINS-CURRENT> 13,881,504
<APPREC-INCREASE-CURRENT> 113,792,847
<NET-CHANGE-FROM-OPS> 141,531,614
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 35,000
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 3,762,641
<NUMBER-OF-SHARES-REDEEMED> 879,910
<SHARES-REINVESTED> 1,621,795
<NET-CHANGE-IN-ASSETS> 239,082,412
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 9,200
<OVERDIST-NET-GAINS-PRIOR> 56,602
<GROSS-ADVISORY-FEES> 1,882,599
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 1,944,195
<AVERAGE-NET-ASSETS> 954,882,895
<PER-SHARE-NAV-BEGIN> 20.520
<PER-SHARE-NII> 0.311
<PER-SHARE-GAIN-APPREC> 2.985
<PER-SHARE-DIVIDEND> 0.001
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 23.815
<EXPENSE-RATIO> 0.20
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</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> 6-MOS
<FISCAL-YEAR-END> DEC-31-1995
<PERIOD-END> JUN-30-1995
<INVESTMENTS-AT-COST> 101,111,713
<INVESTMENTS-AT-VALUE> 101,111,713
<RECEIVABLES> 1,931
<ASSETS-OTHER> 5,816
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 101,119,460
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 585,000
<TOTAL-LIABILITIES> 585,000
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 99,529,116
<SHARES-COMMON-STOCK> 100,534,460
<SHARES-COMMON-PRIOR> 91,786,033
<ACCUMULATED-NII-CURRENT> 8,913
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 100,534,460
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 2,870,986
<OTHER-INCOME> 0
<EXPENSES-NET> 253,781
<NET-INVESTMENT-INCOME> 2,617,205
<REALIZED-GAINS-CURRENT> (20)
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 2,617,185
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 2,617,185
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 27,928,570
<NUMBER-OF-SHARES-REDEEMED> 21,744,685
<SHARES-REINVESTED> 2,564,542
<NET-CHANGE-IN-ASSETS> 8,748,427
<ACCUMULATED-NII-PRIOR> 8,893
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (8,893)
<GROSS-ADVISORY-FEES> 235,080
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 253,781
<AVERAGE-NET-ASSETS> 94,812,415
<PER-SHARE-NAV-BEGIN> 1.000
<PER-SHARE-NII> 0.028
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> 0.028
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 1.000
<EXPENSE-RATIO> 0.28
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000067160
<NAME> MML SERIES INVESTMENT FUND
<SERIES>
<NUMBER> 3
<NAME> MML MANAGED BOND FUND
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1995
<PERIOD-END> JUN-30-1995
<INVESTMENTS-AT-COST> 136,268,301
<INVESTMENTS-AT-VALUE> 139,449,950
<RECEIVABLES> 2,489,472
<ASSETS-OTHER> 5,961
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 141,945,383
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 180,771
<TOTAL-LIABILITIES> 180,771
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 138,595,460
<SHARES-COMMON-STOCK> 11,573,563
<SHARES-COMMON-PRIOR> 10,879,319
<ACCUMULATED-NII-CURRENT> 2,284,781
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (2,414,572)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 3,183,207
<NET-ASSETS> 141,764,612
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 4,826,053
<OTHER-INCOME> 0
<EXPENSES-NET> 339,719
<NET-INVESTMENT-INCOME> 4,486,334
<REALIZED-GAINS-CURRENT> (244,458)
<APPREC-INCREASE-CURRENT> 10,458,246
<NET-CHANGE-FROM-OPS> 14,700,122
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 2,198,282
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 862,543
<NUMBER-OF-SHARES-REDEEMED> 550,609
<SHARES-REINVESTED> 382,310
<NET-CHANGE-IN-ASSETS> 20,554,960
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (2,170,114)
<OVERDISTRIB-NII-PRIOR> 3,270
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 318,697
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 339,719
<AVERAGE-NET-ASSETS> 131,689,974
<PER-SHARE-NAV-BEGIN> 11.141
<PER-SHARE-NII> 0.395
<PER-SHARE-GAIN-APPREC> 0.910
<PER-SHARE-DIVIDEND> 0.197
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 12.249
<EXPENSE-RATIO> 0.26
<AVG-DEBT-OUTSTANDING> 0
<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> 6-MOS
<FISCAL-YEAR-END> DEC-31-1995
<PERIOD-END> JUN-30-1995
<INVESTMENTS-AT-COST> 1,388,254,969
<INVESTMENTS-AT-VALUE> 1,679,351,915
<RECEIVABLES> 10,307,716
<ASSETS-OTHER> 4,364,891
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,694,024,552
<PAYABLE-FOR-SECURITIES> 5,728,889
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 1,577,673
<TOTAL-LIABILITIES> 7,306,562
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,366,511,202
<SHARES-COMMON-STOCK> 85,736,321
<SHARES-COMMON-PRIOR> 81,725,935
<ACCUMULATED-NII-CURRENT> 17,602,007
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 7,703,768
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 294,043,621
<NET-ASSETS> 1,686,717,960
<DIVIDEND-INCOME> 12,909,367
<INTEREST-INCOME> 23,881,001
<OTHER-INCOME> 0
<EXPENSES-NET> 3,032,505
<NET-INVESTMENT-INCOME> 33,757,863
<REALIZED-GAINS-CURRENT> 8,736,078
<APPREC-INCREASE-CURRENT> 143,523,784
<NET-CHANGE-FROM-OPS> 186,017,724
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 16,157,864
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 2,926,863
<NUMBER-OF-SHARES-REDEEMED> 2,334,261
<SHARES-REINVESTED> 3,417,784
<NET-CHANGE-IN-ASSETS> 242,456,823
<ACCUMULATED-NII-PRIOR> 2,008
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 1,032,310
<GROSS-ADVISORY-FEES> 2,980,434
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 3,032,505
<AVERAGE-NET-ASSETS> 1,586,982
<PER-SHARE-NAV-BEGIN> 17.672
<PER-SHARE-NII> 0.397
<PER-SHARE-GAIN-APPREC> 1.796
<PER-SHARE-DIVIDEND> 0.192
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 19.673
<EXPENSE-RATIO> 0.38
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0
</TABLE>
