<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
this schedule contains summary financial information extracted from mason street
funds, inc. municipal bond fund, 09/30/00 financial statement class b.
</LEGEND>
<CIK> 0001023744
<NAME> MASON STREET FUNDS, INC.
<SERIES>
<NUMBER> 032
<NAME> MUNICIPAL BOND FUND CLASS B
<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> 36,266,262
<INVESTMENTS-AT-VALUE> 36,780,082
<RECEIVABLES> 1,529,784
<ASSETS-OTHER> 161,731
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 38,471,597
<PAYABLE-FOR-SECURITIES> 2,614,213
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 262,458
<TOTAL-LIABILITIES> 2,876,671
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 35,033,394
<SHARES-COMMON-STOCK> 81,063
<SHARES-COMMON-PRIOR> 87,124
<ACCUMULATED-NII-CURRENT> 33,521
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 14,191
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 513,820
<NET-ASSETS> 35,594,926
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 963,859
<OTHER-INCOME> 0
<EXPENSES-NET> (149,368)
<NET-INVESTMENT-INCOME> 814,491
<REALIZED-GAINS-CURRENT> 71,008
<APPREC-INCREASE-CURRENT> 625,453
<NET-CHANGE-FROM-OPS> 1,510,952
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (17,023)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 1,966
<NUMBER-OF-SHARES-REDEEMED> 8,027
<SHARES-REINVESTED> 0
<NET-CHANGE-IN-ASSETS> 1,230,536
<ACCUMULATED-NII-PRIOR> 34,006
<ACCUMULATED-GAINS-PRIOR> (57,065)
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 52,826
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 203,733
<AVERAGE-NET-ASSETS> 845,508
<PER-SHARE-NAV-BEGIN> 10.07
<PER-SHARE-NII> 0.21
<PER-SHARE-GAIN-APPREC> (0.01)
<PER-SHARE-DIVIDEND> 0.00
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 10.27
<EXPENSE-RATIO> 1.50
</TABLE>
