<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE 
UNAUDITED CONSOLIDATED FINANCIAL STATEMENTS OF COSTILLA ENERGY INC. FOR THE NINE
MONTHS ENDED SEPTEMBER 30, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1998
<PERIOD-START>                             JAN-01-1998
<PERIOD-END>                               SEP-30-1998
<CASH>                                           6,361
<SECURITIES>                                         0
<RECEIVABLES>                                   11,524
<ALLOWANCES>                                         0
<INVENTORY>                                          0
<CURRENT-ASSETS>                                18,996
<PP&E>                                         329,190
<DEPRECIATION>                                  93,775
<TOTAL-ASSETS>                                 263,231
<CURRENT-LIABILITIES>                           36,457
<BONDS>                                        207,362
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          5
<COMMON>                                           967
<OTHER-SE>                                      18,440
<TOTAL-LIABILITY-AND-EQUITY>                   263,231
<SALES>                                         48,824
<TOTAL-REVENUES>                                49,671
<CGS>                                           21,208
<TOTAL-COSTS>                                   28,544
<OTHER-EXPENSES>                                21,896
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                              14,622
<INCOME-PRETAX>                               (23,248)
<INCOME-TAX>                                         0
<INCOME-CONTINUING>                           (23,248)
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                  (299)
<CHANGES>                                            0
<NET-INCOME>                                  (24,854)
<EPS-PRIMARY>                                   (2.49)
<EPS-DILUTED>                                   (2.49)