<TABLE> <S> <C>

<ARTICLE> 6
<CIK> 0000320282
<NAME> SMITH BARNEY MUNICIPAL MONEY MARKET FUND, INC. CLASS Y
       
<S>                             <C>
<PERIOD-TYPE>                   YEAR
<FISCAL-YEAR-END>                          MAR-31-1998
<PERIOD-END>                               MAR-31-1998
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<SHARES-COMMON-STOCK>                          489,251
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<DIVIDEND-INCOME>                                    0
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<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                       13,931
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<EXPENSE-RATIO>                                  0.540
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                                 0
        


</TABLE>