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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549



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FORM 20-F/A

Amendment No. 1



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(Mark One)



| ̈ | REGISTRATION STATEMENT PURSUANT TO SECTION 12(b) OR (g) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ----------------------------------------------------------------------------------------------



OR



|x | ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ------------------------------------------------------------------------------------



For the fiscal year ended December 31, 2003



OR



| ̈ | TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934
|- | ----------------------------------------------------------------------------------------



For the transition period from
 to



Commission file number 1-14544



Grupo Imsa, S.A. de C.V.

(Exact name
of Registrant as specified in its charter)



Imsa Group

(Translation of Registrants name into English)



United Mexican States

(Jurisdiction of incorporation or organization)



Ave. Batallón de San Patricio No. 111, Piso 26

Fracc. Valle Oriente, San Pedro, Garza
García, N.L. 66269, Mexico

(Address of principal executive offices)



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Securities registered or to be registered pursuant to Section 12(b) of the Act.



|                                                                                                                    |  |                                          
|------------------------------------------------------------------------------------------------------------------- |  | -----------------------------------------
|Title of each class                                                                                                 |  | Name of each exchange on which registered
|American Depositary Shares representing Equity Units                                                                |  | New York Stock Exchange                  
|                                                                                                                    | 
|Equity Units each representing three Series B Shares, without par value, and two Series C Shares, without par value |  | New York Stock Exchange*                 



|* | Not for trading, but only in connection with the registration of American Depositary Shares which are evidenced by American Depositary Receipts.
|- | ------------------------------------------------------------------------------------------------------------------------------------------------



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Securities registered or to be registered pursuant to Section 12(g) of the Act.



Not applicable

(Title of Class)



Securities for which there is a reporting obligation
pursuant to Section 15(d) of the Act.



Not applicable

(Title of Class)



Indicate the number of outstanding shares of each of the issuers classes of capital or common stock as of the close of the period covered by the
annual report.



|                                   |  |              
|---------------------------------- |  | -------------
|Series B Shares, without par value |  | 2,337,103,674
|Series C Shares, without par value |  | 478,069,116  



Indicate by check mark
whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports),
and (2) has been subject to such filing requirements for the past 90 days.



Yes  x    No ̈



Indicate by check mark which financial statement item the registrant has
elected to follow.



Item 17 ̈Item 18  x

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1



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EXPLANATORY NOTE



We are amending our Annual Report on Form 20-F for the year ended December 31, 2003 (the Annual Report) to
delete the footnote to the agreement referenced in Item 19 and identified as Exhibit 4.2 (the 4.2 Agreement), which provided that certain information from the 4.2 Agreement had been omitted pursuant to a request for confidential
treatment and had been filed separately with the Securities Exchange Commission. Pursuant to Rule 12b-15 under the Securities and Exchange Act of 1934, this amendment to the Annual Report includes Item 19 in its entirety, notwithstanding the fact
that it is identical to Item 19 of the Annual Report, except for the deletion referenced in the first sentence of this paragraph.



No other changes are being made to the Annual Report, as originally filed. The Annual Report, as amended by this amendment, continues to speak as of the
date of its original filing, and we have not updated the disclosure as of a later date.



|Item 19 | Exhibits
|------- | --------



The following exhibits are filed as part of this annual report:



|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |  |           
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | ----------
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |  | ExhibitNo.
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | 
|By-laws (Estatutos Sociales), as amended (English translation).*                                                                                                                                                                                                                                                                                                                                                                                                                              |  | 1.1       
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | 
|Credit Agreement, dated as of August 22, 2000, as amended and restated as of December 11, 2001, among Grupo Imsa, S.A. de C.V., the Initial Lenders named therein, Salomon Smith Barney Inc., as
Lead Arranger and Syndication Agent and Citibank, N.A., as Administrative Agent (incorporated by reference to the Companys Annual Report on Form 20-F filed on July 1, 2002).1                                                                                                              |  | 4.1       
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | 
|Credit and Security Agreement, dated as of May 4, 2001, as amended and restated as of October 31, 2002, and as further amended and restated as of March 15, 2004 among Enertec Mexico, S. de R.L.
de C.V. and Enertec Exports, S. de R.L. de C.V. and the Lenders therein, JPMorgan Chase Bank, as Collateral Agent, and ING (U.S.) Capital LLC, as Administrative Agent (incorporated by reference to the amendment to the Companys Annual Report on
Form 20-F/A filed on October 8, 2004). |  | 4.2       
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | 
|Asset Purchase Agreement, dated as of August 21, 2001, by and among Varco Pruden Buildings, Inc., VP-Graham, Inc., Varco Pruden International, Inc. and United Panel, Inc., as Sellers, and Grupo
Imsa, S.A. de C.V. as Buyer, and The LTV Corporation (incorporated by reference to the Companys Annual Report on Form 20-F filed on July 1, 2002).1                                                                                                                                        |  | 4.3       
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | 
|Subsidiaries of the Company.*                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |  | 8.1       
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | 
|Certification of Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.*                                                                                                                                                                                                                                                                                                                                                                                          |  | 12.1      
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | 
|Certification of Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.*                                                                                                                                                                                                                                                                                                                                                                                          |  | 12.2      
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | 
|Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.*                                                                                                                                                                                                                                                                                                                                           |  | 13.1      
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              | 
|Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.*                                                                                                                                                                                                                                                                                                                                           |  | 13.2      

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|* | Filed herewith.
|- | ---------------



|1 | Confidential treatment was granted by the Securities Exchange Commission for a portion of this document.
|- | --------------------------------------------------------------------------------------------------------





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SIGNATURE



The registrant hereby certifies that it meets all the requirements for filing on Form 20-F/A and that it has duly caused and authorized the undersigned
to sign this report on its behalf.



GRUPO IMSA, S.A. DE C.V.By:

/s/ Enrique González GonzálezName: Enrique González González Title: General Counsel




Dated: October 8, 2004





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INDEX TO EXHIBITS



|                                                                                                     |  |           
|---------------------------------------------------------------------------------------------------- |  | ----------
|                                                                                                     |  | ExhibitNo.
|                                                                                                     | 
|Certification of Chief Executive Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.* |  | 12.1      
|                                                                                                     | 
|Certification of Chief Financial Officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.* |  | 12.2      

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|* | Filed herewith.
|- | ---------------