1

PROSPECTUS SUPPLEMENT                       This Prospectus Supplement,        
FOR THE PERIOD ENDING                       filed pursuant to Rule 424(b)(3),  
JULY 31, 1997 TO                            relates to Registration Statement  
PROSPECTUS DATED                            No. 33-43136-02 and the            
OCTOBER 8, 1991                             Prospectus dated October 8, 1991   




                       SECURITIES AND EXCHANGE COMMISSION
                             450 Fifth Street, N.W.
                             Washington, D.C. 20549


                                    FORM 8-K

                                 CURRENT REPORT

                     Pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934


        Date of Report (Date of earliest event reported): August 15, 1997


                           DISCOVER CARD TRUST 1991 D
                           --------------------------
             (Exact name of registrant as specified in its charter)


Delaware                        0-19734                     Not Applicable
- --------                        -------                     --------------
(State of                       (Commission                 (IRS Employer
organization)                   File Number)                Identification No.)


c/o Discover Receivables Financing Group, Inc.
12 Read's Way
New Castle, Delaware                                            19720
- ------------------------------------------------------------------------
(Address of principal executive offices)                      (Zip Code)

Registrant's telephone number, including area code: (302) 323-7826


                                 Not Applicable
          -------------------------------------------------------------
          (Former name or former address, if changed since last report)


                                  Page 1 of 15
                         Index to Exhibits is on page 4


   2

Item 5. Other Events

On August 15, 1997 the Registrant made available the Monthly Certificateholders'
Statement for the Due Period of July 1997, which is attached as Exhibit 21
hereto.

Item 7.  Financial Statements and Exhibits

(c) Exhibits

Exhibit No.         Description

21                  Monthly Certificateholders' Statement for Discover Card
                    Trust 1991 D related to the Due Period ending July 31, 1997.



















   3

                                   SIGNATURES

         Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized.



                                       DISCOVER CARD TRUST 1991 D
                                              (Registrant)

                                       By: DISCOVER RECEIVABLES FINANCING
                                           GROUP, INC.
                                           as originator of the Trust


                                       By: Birendra Kumar
                                           ----------------------------
                                           Birendra Kumar
                                           Vice President and Treasurer


Date: August 15, 1997











   4

                                  EXHIBIT INDEX

Exhibit No.         Description

21                  Monthly Certificateholders' Statement for Discover Card
                    Trust 1991 D related to the Due Period ending July 31, 1997.