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

<TABLE> <S> <C>

<ARTICLE> 6
<CIK> 0000880366
<NAME> SMITH BARNEY INVESTMENT FUNDS
<SERIES>
   <NUMBER> 4
   <NAME> LARGE CAPITALIZATION GROWTH FUND - CLASS Y

<S>                             <C>
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          NOV-30-2000
<PERIOD-END>                               MAY-31-2000
<INVESTMENTS-AT-COST>                    2,947,160,520
<INVESTMENTS-AT-VALUE>                   4,126,800,000
<RECEIVABLES>                                8,430,291
<ASSETS-OTHER>                                     261
<OTHER-ITEMS-ASSETS>                                 0
<TOTAL-ASSETS>                           4,135,230,552
<PAYABLE-FOR-SECURITIES>                             0
<SENIOR-LONG-TERM-DEBT>                              0
<OTHER-ITEMS-LIABILITIES>                    4,482,792
<TOTAL-LIABILITIES>                          4,482,792
<SENIOR-EQUITY>                                      0
<PAID-IN-CAPITAL-COMMON>                 2,946,339,722
<SHARES-COMMON-STOCK>                        8,266,342
<SHARES-COMMON-PRIOR>                        7,720,933
<ACCUMULATED-NII-CURRENT>                 (18,018,198)
<OVERDISTRIBUTION-NII>                               0
<ACCUMULATED-NET-GAINS>                     22,786,756
<OVERDISTRIBUTION-GAINS>                             0
<ACCUM-APPREC-OR-DEPREC>                 1,179,639,480
<NET-ASSETS>                             4,130,747,760
<DIVIDEND-INCOME>                           13,162,445
<INTEREST-INCOME>                              271,886
<OTHER-INCOME>                                       0
<EXPENSES-NET>                              31,452,529
<NET-INVESTMENT-INCOME>                   (18,018,198)
<REALIZED-GAINS-CURRENT>                    22,839,597
<APPREC-INCREASE-CURRENT>                  241,130,529
<NET-CHANGE-FROM-OPS>                      245,951,928
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                            0
<DISTRIBUTIONS-OF-GAINS>                       293,311
<DISTRIBUTIONS-OTHER>                                0
<NUMBER-OF-SHARES-SOLD>                        546,333
<NUMBER-OF-SHARES-REDEEMED>                        924
<SHARES-REINVESTED>                                  0
<NET-CHANGE-IN-ASSETS>                     711,704,975
<ACCUMULATED-NII-PRIOR>                              0
<ACCUMULATED-GAINS-PRIOR>                    5,736,115
<OVERDISTRIB-NII-PRIOR>                              0
<OVERDIST-NET-GAINS-PRIOR>                           0
<GROSS-ADVISORY-FEES>                       14,644,537
<INTEREST-EXPENSE>                                   0
<GROSS-EXPENSE>                             31,452,529
<AVERAGE-NET-ASSETS>                       205,371,421
<PER-SHARE-NAV-BEGIN>                            24.14
<PER-SHARE-NII>                                   0.00
<PER-SHARE-GAIN-APPREC>                           1.80
<PER-SHARE-DIVIDEND>                              0.00
<PER-SHARE-DISTRIBUTIONS>                         0.04
<RETURNS-OF-CAPITAL>                              0.00
<PER-SHARE-NAV-END>                              25.90
<EXPENSE-RATIO>                                   0.75


</TABLE>