[ARTICLE] 6
[CIK] 0000355747
[NAME] SMITH BARNEY INVESTMENT FUNDS INC.
[SERIES]
   [NUMBER] 1
   [NAME] INVESTMENT GRADE BOND FUND, CLASS B
<TABLE>
<S>                             <C>
[PERIOD-TYPE]                   6-MOS
[FISCAL-YEAR-END]                          DEC-31-1998
[PERIOD-END]                               JUN-30-1998
[INVESTMENTS-AT-COST]                      534,093,674
[INVESTMENTS-AT-VALUE]                     587,463,816
[RECEIVABLES]                               11,033,913
[ASSETS-OTHER]                                       0
[OTHER-ITEMS-ASSETS]                                 0
[TOTAL-ASSETS]                             598,467,729
[PAYABLE-FOR-SECURITIES]                             0
[SENIOR-LONG-TERM-DEBT]                              0
[OTHER-ITEMS-LIABILITIES]                    6,708,641
[TOTAL-LIABILITIES]                          6,708,641
[SENIOR-EQUITY]                                      0
[PAID-IN-CAPITAL-COMMON]                   521,996,807
[SHARES-COMMON-STOCK]                       18,505,428
[SHARES-COMMON-PRIOR]                       18,898,019
[ACCUMULATED-NII-CURRENT]                    (694,919)
[OVERDISTRIBUTION-NII]                               0
[ACCUMULATED-NET-GAINS]                     17,187,058
[OVERDISTRIBUTION-GAINS]                             0
[ACCUM-APPREC-OR-DEPREC]                    53,370,142
[NET-ASSETS]                               591,759,088
[DIVIDEND-INCOME]                                    0
[INTEREST-INCOME]                           19,146,337
[OTHER-INCOME]                                       0
[EXPENSES-NET]                               3,442,033
[NET-INVESTMENT-INCOME]                     15,704,304
[REALIZED-GAINS-CURRENT]                    17,085,593
[APPREC-INCREASE-CURRENT]                      342,109
[NET-CHANGE-FROM-OPS]                       33,132,006
[EQUALIZATION]                                       0
[DISTRIBUTIONS-OF-INCOME]                    6,841,163
[DISTRIBUTIONS-OF-GAINS]                        25,807
[DISTRIBUTIONS-OTHER]                                0
[NUMBER-OF-SHARES-SOLD]                      2,077,327
[NUMBER-OF-SHARES-REDEEMED]                  2,799,329
[SHARES-REINVESTED]                            329,411
[NET-CHANGE-IN-ASSETS]                      41,505,563
[ACCUMULATED-NII-PRIOR]                       (14,263)
[ACCUMULATED-GAINS-PRIOR]                       62,342
[OVERDISTRIB-NII-PRIOR]                              0
[OVERDIST-NET-GAINS-PRIOR]                           0
[GROSS-ADVISORY-FEES]                        1,816,328
[INTEREST-EXPENSE]                                   0
[GROSS-EXPENSE]                              3,442,033
[AVERAGE-NET-ASSETS]                       248,117,546
[PER-SHARE-NAV-BEGIN]                            13.19
[PER-SHARE-NII]                                  00.34
[PER-SHARE-GAIN-APPREC]                          00.41
[PER-SHARE-DIVIDEND]                             00.37
[PER-SHARE-DISTRIBUTIONS]                            0
[RETURNS-OF-CAPITAL]                                 0
[PER-SHARE-NAV-END]                              13.57
[EXPENSE-RATIO]                                  01.51
[AVG-DEBT-OUTSTANDING]                               0
[AVG-DEBT-PER-SHARE]                                 0
</TABLE>