UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                                   FORM F-X

          APPOINTMENT OF AGENT FOR SERVICE OF PROCESS AND UNDERTAKING

A.   Name of issuer or person filing ("Filer"): CEMEX, S.A. de C.V.

B.   This is [check one]

     [X]     an original filing for the Filer

     [ ]     an amended filing for the Filer

C.  Identify the filing in conjunction with which this Form is being filed:

           Name of registrant                 CEMEX, S.A. de C.V.
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           Form type                          Form  CB
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           File Number (if known)             Not Available
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           Filed by                           CEMEX, S.A. de C.V.
                                ------------------------------------------------
            

           Date Filed (if filed concurrently, so indicate)   December 3, 2004,
                                                             concurrently with 
                                                             Form CB
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D.  The Filer is incorporated or organized under the laws of (Name of the 
    jurisdiction under whose laws the issuer is organized or incorporated) 
    UNITED MEXICAN STATES  and has its principal place of business at 
    (Address in full and telephone number) 

         Av. Ricardo Margain Zozaya #325, Colonia del Valle Campestre
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         Garza Garcia, Nuevo Leon, Mexico 66265 (Tel) +5281-8888-8888
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E.  The Filer designates and appoints (Name of United States person serving as
    agent) JILL SIMEONE ("Agent") located at (Address in full in the United
    States and telephone number) CEMEX NY CORP., 590 MADISON AVENUE, 41ST
    FLOOR, NEW YORK, NEW YORK 10022, U.S.A. (Tel) +1-212-317-6000 as the agent
    of the Filer upon whom may be served any process, pleadings, subpoenas, or
    other papers in 

    (a)   any investigation or administrative proceeding conducted by the
          Commission; and 

    (b)   any civil suit or action brought against the Filer or to which the
          Filer has been joined as defendant or respondent, in any appropriate
          court in any place subject to the jurisdiction of any state or of
          the United States or of any of its territories or possessions or of
          the District of Columbia, where the investigation, proceeding or
          cause of action arises out of or relates to or concerns (i) any
          offering made or purported to be made in connection with the
          securities registered or qualified by the Filer on Form (Name of
          form) CB on (Date) DECEMBER 3, 2004 or any purchases or sales of any
          security in connection therewith; (ii) the securities in relation to
          which the obligation to file an annual report on Form 40-F arises,
          or any purchases or sales of such securities; (iii) any tender offer
          for the securities of a Canadian issuer with respect to which
          filings are made by the Filer with the Commission on Schedule
          13E-4F, 14D-1F or 14D-9F; or (iv) the securities in relation to
          which the Filer acts as trustee pursuant to an exemption under Rule
          10a-5 under the Trust Indenture Act of 1939. The Filer stipulates
          and agrees that any such civil suit or action or administrative
          proceeding may be commenced by the service of process upon, and that
          service of an administrative subpoena shall be effected by service
          upon such agent for service of process, and that service as
          aforesaid shall be taken and held in all courts and administrative
          tribunals to be valid and binding as if personal service thereof had
          been made. 

F.  The Filer stipulates and agrees to appoint a successor agent for service
    of process and file an amended Form F-X if the Filer discharges the Agent
    or the Agent is unwilling or unable to accept service on behalf of the
    Filer at any time until six years have elapsed following the effective
    date of the latest amendment to Form CB, in conjunction with which this
    Form F-X is being filed.

    The Filer further undertakes to advise the Commission promptly of any
    change to the Agent's name or address during the applicable period by
    amendment of this Form, referencing the file number of the relevant form
    in conjunction with which the amendment is being filed. The Filer
    certifies that it has duly caused this power of attorney, consent,
    stipulation and agreement to be signed on its behalf by the undersigned,
    thereunto duly authorized, in the City of GARZA GARCIA   Country of UNITED
    MEXICAN STATES this 3rd day of DECEMBER, 2004. 
       
    Filer:   CEMEX, S.A. de C.V.



                                                    /s/ Rodrigo Trevino        
                                                    ------------------------   
                                                    By:(Signature and Title)
                                                    Rodrigo Trevino
                                                    Chief Financial Officer



This statement has been signed by the following persons in the capacities and
on the dates indicated.

/s/ Jill Simeone
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(Signature)


Jill Simeone, as Agent for Service of Process on behalf of CEMEX, S.A. de C.V.
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(Title)

December 3, 2004
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(Date)