WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.

<TABLE> <S> <C>

<ARTICLE> 6
<CIK> 0000320282
<NAME> SMITH BARNEY MUNICIPAL MONEY MARKET FUND, INC. CLASS C
       
<S>                             <C>
<PERIOD-TYPE>                   YEAR
<FISCAL-YEAR-END>                          MAR-31-1998
<PERIOD-END>                               MAR-31-1998
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<INVESTMENTS-AT-VALUE>                   6,344,977,087
<RECEIVABLES>                               31,978,779
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<PAYABLE-FOR-SECURITIES>                    80,760,000
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                   11,400,440
<TOTAL-LIABILITIES>                         92,160,440
<SENIOR-EQUITY>                                      0
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<SHARES-COMMON-STOCK>                            4,722
<SHARES-COMMON-PRIOR>                            4,651
<ACCUMULATED-NII-CURRENT>                            0
<OVERDISTRIBUTION-NII>                               0
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<OVERDISTRIBUTION-GAINS>                             0
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<DIVIDEND-INCOME>                                    0
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<OTHER-INCOME>                                       0
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<NET-INVESTMENT-INCOME>                    180,135,362
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<APPREC-INCREASE-CURRENT>                            0
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<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                          134
<DISTRIBUTIONS-OF-GAINS>                             0
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<NUMBER-OF-SHARES-SOLD>                              0
<NUMBER-OF-SHARES-REDEEMED>                     10,611
<SHARES-REINVESTED>                                212
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<ACCUMULATED-NII-PRIOR>                              0
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<OVERDISTRIB-NII-PRIOR>                              0
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<EXPENSE-RATIO>                                  0.640
<AVG-DEBT-OUTSTANDING>                               0
<AVG-DEBT-PER-SHARE>                                 0
        


</TABLE>