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                      SECURITIES AND EXCHANGE COMMISSION
                           WASHINGTON, D.C. 20549

                                FORM 10-K/A

          AMENDMENT NO. 1 TO ANNUAL REPORT PURSUANT TO SECTION 13 OF
                     THE SECURITIES EXCHANGE ACT OF 1934

FOR THE FISCAL YEAR ENDED DECEMBER 31, 1997         COMMISSION FILE NO. 1-11792


                        MERCANTILE BANCORPORATION INC.
            (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)

             MISSOURI                                43-0951744
     (STATE OF INCORPORATION)                      (IRS EMPLOYER
                                                 IDENTIFICATION NO.)

             P.O. BOX 524                             63166-0524
          ST. LOUIS, MISSOURI                         (ZIP CODE)
(ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)


       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: 314-418-2525

<TABLE>
<S>                                                           <C>
SECURITIES REGISTERED PURSUANT TO SECTION 12(B) OF THE ACT:   NAME OF EXCHANGE ON WHICH REGISTERED:
     (1) COMMON STOCK ($0.01 PAR VALUE)                       (1) NEW YORK STOCK EXCHANGE
     (2) PREFERRED STOCK PURCHASE RIGHTS                      (2) NEW YORK STOCK EXCHANGE
</TABLE>

      SECURITIES REGISTERED PURSUANT TO SECTION 12(G) OF THE ACT:  NONE

INDICATE BY CHECK MARK WHETHER THE REGISTRANT (1) HAS FILED ALL REPORTS
REQUIRED TO BE FILED BY SECTION 13 OF THE SECURITIES EXCHANGE ACT OF 1934
DURING THE PRECEDING 12 MONTHS, AND (2) HAS BEEN SUBJECT TO SUCH FILING
REQUIREMENTS FOR THE PAST 90 DAYS. YES      X      NO  -----

     INDICATE BY CHECK MARK IF DISCLOSURE OF DELINQUENT FILERS
      PURSUANT TO ITEM 405 OF REGULATION S-K IS NOT CONTAINED
         HEREIN, AND WILL NOT BE CONTAINED, TO THE
          BEST OF REGISTRANT'S KNOWLEDGE, IN DEFINITIVE
           PROXY OR INFORMATION STATEMENTS INCORPORATED
            BY REFERENCE IN PART III OF THIS
                      FORM 10-K.  [X]

     STATE THE AGGREGATE MARKET VALUE OF THE VOTING STOCK HELD
    BY NON-AFFILIATES OF THE REGISTRANT AS OF FEBRUARY 27, 1998:
           COMMON STOCK, $0.01 PAR VALUE, $6,217,819,682

     INDICATE THE NUMBER OF SHARES OUTSTANDING OF EACH OF THE
   REGISTRANT'S CLASSES OF COMMON STOCK, AS OF FEBRUARY 27, 1998:
    COMMON STOCK $0.01 PAR VALUE, 133,748,539 SHARES OUTSTANDING

                 DOCUMENT INCORPORATED BY REFERENCE
         AS PROVIDED HEREIN, PORTIONS OF THE DOCUMENTS BELOW ARE
                     INCORPORATED BY REFERENCE:

<TABLE>
<CAPTION>
                       DOCUMENT                                    PART--FORM 10-K
<S>                                                                <C>
     ANNUAL REPORT OF THE REGISTRANT TO ITS SHAREHOLDERS
     FOR THE YEAR ENDED DECEMBER 31, 1997                          PARTS I, II, IV

     REGISTRANT'S PROXY STATEMENT FOR THE 1998
     ANNUAL MEETING OF SHAREHOLDERS                                PART III
</TABLE>


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The "Exhibit Index" as previously filed with the Form 10-K is hereby amended
by inserting the following entries:

      No. 23-1                Consent of KPMG Peat Marwick LLP (relating to
                              report dated June 26, 1998, Mercantile
                              Bancorporation Inc. Horizon Investment and
                              Savings Plan and Trust Financial Statements.)

      No. 99                  Report of the Independent Auditors KPMG Peat
                              Marwick LLP dated June 24, 1998; Statements of
                              Net Assets Available for Plan Benefits of
                              Mercantile Bancorporation Inc. Horizon
                              Investment and Savings Plan and Trust as of
                              December 31, 1997 and 1996; Statements of
                              Changes in Net Assets Available For Plan
                              Benefits for the years then ended; and the
                              Notes and Schedules thereto.

The Exhibit Index, as amended, follows, and new Exhibits 23-1 and 99 are
filed herewith.


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<TABLE>
                           EXHIBIT INDEX
<CAPTION>

EXHIBIT NO.                                                  DESCRIPTION
<C>               <S>
No. 3-1(a)        Restated Articles of Incorporation of the Registrant, as amended and currently in effect, filed as
                  Exhibit 3 to Registrant's Quarterly Report on Form 10-Q for the quarter ended March 31, 1997, are
                  incorporated herein by reference.

No. 3-1(b)        Third Amended and Restated Certificate of Designation, Preferences and Rights of Series A Junior
                  Participating Preferred Stock of the Registrant.

No. 3-2           By-Laws of the Registrant, as amended and currently in effect, filed as Exhibit 3.2 to Amendment No.
                  2 to Registrant's Registration Statement No. 333-17757, are incorporated herein by reference.

No. 4-1           Form of Indenture Regarding Subordinated Securities between the Registrant and The First National
                  Bank of Chicago as Trustee, filed on March 31, 1992 as Exhibit 4.1 to Registrant's Report on Form 8-K
                  dated September 24, 1992, is incorporated herein by reference.

No. 4-2           Rights Agreement dated as of May 23, 1988, between Registrant and Mercantile Bank National
                  Association, as Rights Agent (including as exhibits thereto the form of Certificate of Designation,
                  Preferences and Rights of Series A Junior Participating Preferred Stock and the form of Rights
                  Certificate) filed as Exhibits 1 and 2 to Registrant's Registration Statement on Form 8-A, dated May
                  24, 1988, is incorporated herein by reference.

No. 4-3           Form of Indenture Regarding Senior Debt Securities, filed as Exhibit 4.1 to Registrant's Registration
                  Statement No. 333-25775, is incorporated herein by reference.

No. 4-4           Form of Indenture Regarding Subordinated Debt Securities, filed as Exhibit 4.2 to Registrant's
                  Registration Statement No. 333-25775, is incorporated herein by reference.

No. 4-5           Indenture, dated February 4, 1997, First Supplemental Indenture, dated February 4, 1997, and
                  Supplemental Indenture of First Supplemental Indenture, dated May 22, 1997, between the Company, as
                  issuer, and The Chase Manhattan Bank, as Indenture Trustee, filed as Exhibits 4.5, 4.6 and 4.12,
                  respectively, to the Company's Registration Statement on Form S-4 (No. 333-25131), are incorporated
                  herein by reference.

No. 10-1          The Mercantile Bancorporation Inc. 1987 Stock Option Plan, as amended, filed as Exhibit 10-3 to
                  Registrant's Report on Form 10-K for the year ended December 31, 1989 (Commission File No. 1-11792),
                  is incorporated herein by reference.<F*>

No. 10-2          The Mercantile Bancorporation Inc. Amended and Restated Executive Incentive Compensation Plan, filed
                  as Annex H to Registrant's definitive Proxy Statement for the 1997 Annual Meeting of Shareholders, is
                  incorporated herein by reference.<F*>

No. 10-3          The Mercantile Bancorporation Inc. Employee Stock Purchase Plan, filed as Exhibit 10-7 to
                  Registrant's Report on Form 10-K for the year ended December 31, 1989 (Commission File No. 1-11792),
                  is incorporated herein by reference.<F*>

No. 10-4          The Mercantile Bancorporation Inc. 1991 Employee Incentive Plan, filed as Exhibit 10-7 to
                  Registrant's Report on Form 10-K for the year ended December 31, 1990 (Commission File No. 1-11792),
                  is incorporated herein by reference.<F*>


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No. 10-5          Amendment Number One to the Mercantile Bancorporation Inc. 1991 Employee Incentive Plan, filed as
                  Exhibit 10-6 to Registrant's Report on Form 10-K for the year ended December 31, 1994, is
                  incorporated herein by reference.<F*>

No. 10-6          The Mercantile Bancorporation Inc. Amended and Restated Stock Incentive Plan, filed as Annex G to
                  Registrant's definitive Proxy Statement for the 1997 Annual Meeting of Shareholders, is incorporated
                  herein by reference.<F*>

No. 10-7          The Mercantile Bancorporation Inc. 1994 Stock Incentive Plan for Non-Employee Directors, filed as
                  Appendix E to Registrant's definitive Proxy Statement for the 1994 Annual Meeting of Shareholders, is
                  incorporated herein by reference.<F*>

No. 10-8          The Mercantile Bancorporation Inc. Amended and Restated Voluntary Deferred Compensation Plan, filed
                  as Exhibit 10.1 to Registrant's Registration Statement on Form S-8 (File No. 333-47713), is
                  incorporated herein by reference.<F*>

No. 10-9          Employment Agreement for Thomas H. Jacobsen, as amended and restated.<F*>

No. 10-10         Form of Change of Control Employment Agreement for John W. McClure, W. Randolph Adams, John Q. Arnold
                  and Certain Other Executive Officers, filed as Exhibit 10-10 to Registrant's Report on Form 10-K for
                  the year ended December 31, 1989 (Commission File No. 1-11792), is incorporated herein by reference.<F*>

No. 10-11         Mercantile Bancorporation Inc. Supplemental Retirement Plan, filed as Exhibit 10-12 to Registrant's
                  Report on Form 10-K for the year ended December 31, 1992, is incorporated herein by reference.<F*>

No. 10-12         Mercantile Bancorporation Inc. Voluntary Deferred Compensation Plan for Non-Employee Affiliate
                  Directors and Advisory Directors, filed as Exhibit 10.3 to Registrant's Registration statement on
                  Form S-8 (File No. 333-47713), is incorporated herein by reference.<F*>

No. 10-13         Mercantile Bancorporation Inc. Amended and Restated Stock Incentive Plan for Non-Employee Directors,
                  filed as Exhibit 10.2 to Registrant's Registration Statement on Form S-8 (File No. 333-47713), is
                  incorporated herein by reference.<F*>

No. 10-14         Agreement and Plan of Reorganization, dated October 27, 1996, by and among Mercantile Bancorporation
                  Inc., Ameribanc, Inc. and Mark Twain Bancshares, Inc., filed as Exhibit 2.1 to Registrant's Report on
                  Form 8-K filed on November 6, 1996, is incorporated herein by reference.

No. 10-15         Amendment to Agreement and Plan of Reorganization, dated January 24, 1997, by and among Registrant,
                  Ameribanc, Inc. and Mark Twain Bancshares, Inc., filed as Exhibit 10-16 to Amendment No. 2 to
                  Registrant's Registration Statement No. 333-17757, is incorporated herein by reference.

No. 10-16         Stock Option Agreement, dated October 27, 1996, by and between Mercantile Bancorporation Inc., as
                  grantee, and Mark Twain Bancshares, Inc., as issuer, filed as Exhibit 2.2 to Registrant's Report on
                  Form 8-K filed on November 6, 1996, is incorporated herein by reference.

No. 10-17         Agreement and Plan of Reorganization, dated December 22, 1996, by and between Mercantile
                  Bancorporation Inc. and Roosevelt Financial Group, Inc., filed as Exhibit 2.1 to Registrant's Report
                  on Form 8-K filed on December 30, 1996, is incorporated herein by reference.


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No. 10-18         Stock Option Agreement, dated December 22, 1996, by and between Mercantile Bancorporation Inc., as
                  grantee, and Roosevelt Financial Group, Inc., as issuer, filed as Exhibit 2.1 to Registrant's Report
                  on Form 8-K filed on December 30, 1996, is incorporated herein by reference.

No. 10-19         Employment Agreement for Alvin J. Siteman, dated November 18, 1996, filed as Exhibit 10.3 to
                  Registrant's Report on Form 10-Q for the quarter ended March 31, 1997, is incorporated herein by
                  reference.<F*>

No. 10-20         Employment Agreement for John P. Dubinsky, dated October 27, 1996, filed as Exhibit 10.4 to
                  Registrant's Report on Form 10-Q for the quarter ended March 31, 1997, is incorporated herein by
                  reference.<F*>

No. 10-21         Employment Agreement for Stanley J. Bradshaw, dated December 22, 1996, filed as Exhibit 10 to
                  Registrant's Report on Form 10-Q for the quarter ended March 31, 1997, is incorporated herein by
                  reference.<F*>

No. 13            Annual Report of the Registrant to its Shareholders for the year ended December 31, 1997.

No. 21            Subsidiaries of the Registrant as of February 27, 1998.

No. 23            Consent of KPMG Peat Marwick LLP.

No. 23-1          Consent of KPMG Peat Marwick LLP (relating to report dated June 26, 1998, Mercantile Bancorporation
                  Inc. Horizon Investment and Savings Plan and Trust Financial Statements.)

No. 24            Power of Attorney (on signature page).

No. 27            Financial Data Schedule.

No. 99            Report of the Independent Auditors KPMG Peat Marwick LLP dated June 24, 1998; Statements of Net
                  Assets Available for Plan Benefits of Mercantile Bancorporation Inc. Horizon Investment and Savings
                  Plan and Trust as of December 31, 1997 and 1996; Statements of Changes in Net Assets Available For
                  Plan Benefits for the years then ended; and the Notes and Schedules thereto.

<FN>
    <F*>Management contract or compensatory plan or arrangement
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                             SIGNATURES

      Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this amendment to be signed on its behalf by
the undersigned, thereunto duly authorized.




                                          MERCANTILE BANCORPORATION INC.
                                          (Registrant)



Date:  June 26, 1998                      By: /s/JOHN Q. ARNOLD
                                             ---------------------------------
                                               John Q. Arnold
                                               Vice Chairman and Chief
                                               Financial Officer


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                              10-K/A

                           EXHIBIT INDEX
                           -------------

<TABLE>
<CAPTION>

EXHIBIT NO.                             Description
-----------                             -----------
<C>               <S>
No. 23-1          Consent of KPMG Peat Marwick LLP (relating to report dated
                  June 26, 1998, Mercantile Bancorporation Inc. Horizon
                  Investment and Savings Plan and Trust Financial Statements.)

No. 99            Report of the Independent Auditors KPMG Peat Marwick LLP
                  dated June 24, 1998; Statement of Net Assets Available for
                  Plan Benefits of the Mercantile Bancorporation Inc. Horizon
                  Investment and Savings Plan and Trust as of December 31,
                  1997 and 1996; Statements of Changes in Net Assets
                  Available for Plan Benefits for the years then ended; and
                  the Notes and Schedules thereto.
</TABLE>