<ARTICLE>                     5
<LEGEND>
This schedule contains summary financial information extracted from Swift Energy
Managed Penions Assets Partnership 1990-D, Ltd.'s balance sheet and statement of
operations  contained  in its Form 10-Q for the quarter ended June 30, 1997 and
is qualified in its entirety by reference to such financial statements.
</LEGEND>
       
                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                              DEC-31-1997
<PERIOD-END>                                   JUN-30-1997
<CASH>                                         47,545
<SECURITIES>                                   0
<RECEIVABLES>                                  36,757
<ALLOWANCES>                                   0
<INVENTORY>                                    0
<CURRENT-ASSETS>                               84,302
<PP&E>                                         2,639,730
<DEPRECIATION>                                 (2,178,883)
<TOTAL-ASSETS>                                 545,149
<CURRENT-LIABILITIES>                          2,633
<BONDS>                                        0
<PREFERRED-MANDATORY>                          0
<PREFERRED>                                    0
<COMMON>                                       0
<OTHER-SE>                                     542,516
<TOTAL-LIABILITY-AND-EQUITY>                   545,149
<SALES>                                        73,569
<TOTAL-REVENUES>                               74,485
<CGS>                                          0
<TOTAL-COSTS>                                  35,501<F1>
<OTHER-EXPENSES>                               0
<LOSS-PROVISION>                               0
<INTEREST-EXPENSE>                             0
<INCOME-PRETAX>                                21,058
<INCOME-TAX>                                   0
<INCOME-CONTINUING>                            21,058
<DISCONTINUED>                                 0
<EXTRAORDINARY>                                0
<CHANGES>                                      0
<NET-INCOME>                                   21,058

<EPS-PRIMARY>                                  0
<EPS-DILUTED>                                  0
<FN>
<F1>Includes lease operating expenses, production taxes and depreciation,
depletion and amortization expense.  Excludes general and administrative and
interest expense.
</FN>