<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000892538
<NAME> SUNAMERICA SERIES TRUST
<SERIES>
<NUMBER> 026
<NAME> SUNAMERICA SERIES TRUST MFS MID-CAP GROWTH PORTFOLIO
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JAN-31-2001
<PERIOD-START> FEB-01-2000
<PERIOD-END> JUL-31-2000
<INVESTMENTS-AT-COST> 247,958,587
<INVESTMENTS-AT-VALUE> 250,330,051
<RECEIVABLES> 4,477,298
<ASSETS-OTHER> 1,760
<OTHER-ITEMS-ASSETS> 64,498
<TOTAL-ASSETS> 254,873,607
<PAYABLE-FOR-SECURITIES> 10,734,212
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 1,391,447
<TOTAL-LIABILITIES> 12,125,659
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 212,866,246
<SHARES-COMMON-STOCK> 12,819,903
<SHARES-COMMON-PRIOR> 5,233,406
<ACCUMULATED-NII-CURRENT> (88,789)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 27,599,027
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 2,371,464
<NET-ASSETS> 242,747,948
<DIVIDEND-INCOME> 88,595
<INTEREST-INCOME> 493,737
<OTHER-INCOME> 0
<EXPENSES-NET> 671,121
<NET-INVESTMENT-INCOME> (88,789)
<REALIZED-GAINS-CURRENT> 22,542,253
<APPREC-INCREASE-CURRENT> (1,704,357)
<NET-CHANGE-FROM-OPS> 20,749,107
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 10,777,507
<NUMBER-OF-SHARES-REDEEMED> (3,191,010)
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 161,111,649
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 5,056,774
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 620,899
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 676,491
<AVERAGE-NET-ASSETS> 165,398,487
<PER-SHARE-NAV-BEGIN> 15.60
<PER-SHARE-NII> (0.01)
<PER-SHARE-GAIN-APPREC> 3.35
<PER-SHARE-DIVIDEND> 0
<PER-SHARE-DISTRIBUTIONS> 0
<RETURNS-OF-CAPITAL> 0
<PER-SHARE-NAV-END> 18.94
<EXPENSE-RATIO> 0.82
</TABLE>
