<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000832545
<NAME> BARR ROSENBERG SERIES TRUST
<SERIES>
<NUMBER> 011
<NAME> AXA ROSENBERG U.S. SMALL CAPITALIZATION FUND
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> MAR-31-2001
<PERIOD-START> APR-01-2000
<PERIOD-END> SEP-30-2000
<INVESTMENTS-AT-COST> 401500168
<INVESTMENTS-AT-VALUE> 451051849
<RECEIVABLES> 5967333
<ASSETS-OTHER> 3905
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 457023087
<PAYABLE-FOR-SECURITIES> 4590915
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 684595
<TOTAL-LIABILITIES> 5275510
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 384208966
<SHARES-COMMON-STOCK> 43542052<F1>
<SHARES-COMMON-PRIOR> 44527709<F1>
<ACCUMULATED-NII-CURRENT> 1018926
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 16968004
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 49551681
<NET-ASSETS> 451747577
<DIVIDEND-INCOME> 3044148
<INTEREST-INCOME> 170218
<OTHER-INCOME> 17259
<EXPENSES-NET> 2637076
<NET-INVESTMENT-INCOME> 594549
<REALIZED-GAINS-CURRENT> 4092581
<APPREC-INCREASE-CURRENT> (10708922)
<NET-CHANGE-FROM-OPS> (6021792)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 0<F1>
<DISTRIBUTIONS-OF-GAINS> 0<F1>
<DISTRIBUTIONS-OTHER> 0<F1>
<NUMBER-OF-SHARES-SOLD> 5006939
<NUMBER-OF-SHARES-REDEEMED> 5941368
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> (15423214)
<ACCUMULATED-NII-PRIOR> 424377
<ACCUMULATED-GAINS-PRIOR> 12875423
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 2046702
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 2857409
<AVERAGE-NET-ASSETS> 435103845<F1>
<PER-SHARE-NAV-BEGIN> 10.06<F1>
<PER-SHARE-NII> 0.01<F1>
<PER-SHARE-GAIN-APPREC> (0.14)<F1>
<PER-SHARE-DIVIDEND> 0.00<F1>
<PER-SHARE-DISTRIBUTIONS> 0.00<F1>
<RETURNS-OF-CAPITAL> 0.00<F1>
<PER-SHARE-NAV-END> 9.93<F1>
<EXPENSE-RATIO> 1.15<F1>
<FN>
<F1> Institutional Shares
</FN>
</TABLE>
