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                                                                     EXHIBIT 5.1

                      [ANDREWS & KURTH L.L.P. LETTERHEAD]



                                 August 9, 1999

Board of Directors
Santa Fe Snyder Corporation
840 Gessner
Suite 1400
Houston, Texas  77024

Ladies and Gentlemen:

                  We have acted as counsel to Santa Fe Snyder Corporation, a
Delaware corporation (the "Company"), in connection with (i) the preparation and
filing with the Securities and Exchange Commission (the "Commission") under the
Securities Act of 1933, as amended (the "Act"), of the Registration Statement on
Form S-3 filed by the Company with the Commission on May 11, 1999, as amended on
July 8, 1999 (the "Registration Statement"), for the purpose of registering
under the Act, among other securities, equity securities of the Company; and
(ii) the preparation of a prospectus supplement dated August 3, 1999 (the
"Prospectus Supplement") in connection with the issuance of up to 12,650,000
shares (the "Shares") of common stock, par value $.01 per share (the "Common
Stock"), of the Company. The Shares include 1,650,000 shares being offered by
the Company which may be sold pursuant to an over-allotment option granted to
the Underwriters named in the Prospectus Supplement.

                  As the basis for the opinion hereinafter expressed, we have
examined such statutes, regulations, corporate records and documents,
certificates of corporate and public officials, and other instruments as we have
deemed necessary or advisable for the purposes of this opinion. In such
examination we have assumed the authenticity of all documents submitted to us as
originals and the conformity with the original documents of all documents
submitted to us as copies.

                  Based on the foregoing and having due regard for such legal
considerations as we deem relevant, we are of the opinion that the shares have
been duly authorized and, when sold in the manner described in the Registration
Statement, the Prospectus Supplement and the Underwriting Agreement described
therein, will be legally issued and constitute fully paid and nonassessable
shares of Common Stock.

                  This opinion is limited in all respects to the General
Corporation Law of the State of Delaware and the laws of the United States of
America insofar as such laws are applicable.



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                  We hereby consent to the filing of this opinion as an exhibit
to the Registration Statement and to the reference to this firm under the
heading "Legal Opinions" in the Registration Statement and under the heading
"Validity of Securities" in the Prospectus Supplement without admitting that we
are "experts" under the Securities Act of 1933, as amended, or the rules and
regulations of the Commission issued thereunder, with respect to any part of the
Registration Statement, including this exhibit.

                                                     Very truly yours,

                                                     /s/ Andrews & Kurth L.L.P.




1198/1210/2677/2716