<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM 
THE UNAUDITED CONSOLIDATED FINANCIAL STATEMENTS OF COSTILLA ENERGY INC. FOR THE
SIX MONTHS ENDED JUNE 30, 1998 AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO
SUCH FINANCIAL STATEMENTS.
</LEGEND>
<CIK> 0001018980
<NAME> COSTILLA ENERGY INC.
<MULTIPLIER> 1,000
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1998
<PERIOD-START>                             JAN-01-1998
<PERIOD-END>                               JUN-30-1998
<CASH>                                          17,089
<SECURITIES>                                         0
<RECEIVABLES>                                   11,035
<ALLOWANCES>                                         0
<INVENTORY>                                          0
<CURRENT-ASSETS>                                29,563
<PP&E>                                         285,708
<DEPRECIATION>                                  86,242
<TOTAL-ASSETS>                                 238,258
<CURRENT-LIABILITIES>                           25,286
<BONDS>                                        182,441
<PREFERRED-MANDATORY>                                5
<PREFERRED>                                          0
<COMMON>                                           998
<OTHER-SE>                                      29,215
<TOTAL-LIABILITY-AND-EQUITY>                   238,258
<SALES>                                         32,015
<TOTAL-REVENUES>                                32,712
<CGS>                                           14,226
<TOTAL-COSTS>                                   19,454
<OTHER-EXPENSES>                                14,364
<LOSS-PROVISION>                                     0
<INTEREST-EXPENSE>                               9,833
<INCOME-PRETAX>                               (16,009)
<INCOME-TAX>                                         0
<INCOME-CONTINUING>                           (16,009)
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                  (299)
<CHANGES>                                            0
<NET-INCOME>                                  (16,615)
<EPS-PRIMARY>                                   (1.66)
<EPS-DILUTED>                                   (1.66)