<TABLE> <S> <C>

<ARTICLE> 6
<CIK> 0000078713
<NAME> PIONEER FUND
<SERIES>
   <NUMBER> 003
   <NAME> PIONEER FUND CLASS C
<CURRENCY> US

<S>                             <C>
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-2000
<PERIOD-END>                               JUN-30-2000
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<SENIOR-LONG-TERM-DEBT>                              0
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<APPREC-INCREASE-CURRENT>                  (215080558)
<NET-CHANGE-FROM-OPS>                        280632618
<EQUALIZATION>                                       0
<DISTRIBUTIONS-OF-INCOME>                            0
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<PER-SHARE-NII>                                 (0.07)
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<RETURNS-OF-CAPITAL>                                 0
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<EXPENSE-RATIO>                                   1.95


</TABLE>