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                           BUTLER & BINION, L. L. P.
 
                                  SUITE 1600                 WASHINGTON, D.C.
                                1000 LOUISIANA                (202) 466-6900 
ATTORNEYS AT LAW           HOUSTON, TEXAS 77002-5093                  --     
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                                (713) 237-3111                (214) 220-3100 
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                                                                SAN ANTONIO  
                                                              (210) 227-2200 
                
                               December 23, 1996


Nuevo Energy Company
1331 Lamar, Suite 1650
Houston, Texas 77010

Gentlemen:

     We have acted as counsel for Nuevo Financing I, a statutory business trust
created under the laws of the State of Delaware (the "Trust"), in connection
with the issuance and sale of an aggregate of 2,300,000 of its $2.875 Term
Convertible Securities, Series A (the "Trust Preferred Securities"), to be sold
by the Trust in a public offering.  We have also acted as counsel for Nuevo
Energy Company, a Delaware corporation (the "Company"), in connection with its
corresponding (a) guarantee of the Trust Preferred Securities to the extent
described in the Preferred Securities Guarantee Agreement (the "Guarantee")
dated December 23, 1996, and (b) issuance and sale to the Trust, in
consideration and exchange for the proceeds of the issuance and sale of the
Trust Preferred Securities, of its 5.75% Convertible Subordinated Debentures due
December 15, 2026 (the "Convertible Debentures") under a Subordinated Indenture
(the "Base Indenture") dated as of November 25, 1996 between the Company and
Wilmington Trust Company, as trustee, as supplemented by the First Supplemental
Subordinated Indenture dated December 23, 1996 (the "Supplemental Indenture,"
and together with the Base Indenture, the "Indenture"). In addition, we have
acted as counsel for the Company in connection with the sale by United Investors
Management Company ("United") and The 1818 Fund, L.P. (the "1818 Fund" and,
together with United, the "Selling Stockholders") of 2,138,605 shares (the
"Shares") of common stock, $.01 par value per share ("Common Stock") of the
Company.

     Upon delivery by a holder of TECONS of a TECONS to the property trustee of
the Trust, together with an irrevocable conversion notice, the property trustee,
as conversion agent, shall be obligated, on behalf of such holder, to exchange
such TECONS for an equivalent amount of the Convertible Debentures and
immediately convert such amount of the Convertible Debentures into shares
("TECONS Shares") of Common Stock.

     All of the 1,275,000 Shares to be sold by United and 112 of the Shares to
be sold by the 1818 Fund were outstanding (the "Outstanding Shares") prior to
the public offering thereof.  In addition, 863,493 of the Shares to be sold by
the 1818 Fund (the "Conversion Shares") are to be issued upon conversion of
11,220 shares of 7% Cumulative Convertible Preferred Stock, Series A ("Preferred
Stock"), of the Company.
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Nuevo Energy Company
1331 Lamar, Suite 1650
Houston, Texas 77010
Page 2

     We have made such inquiries and examined such documents as we have
considered necessary or appropriate for the purposes of giving the opinions
hereinafter set forth, including the examination of executed or conformed
counterparts, or copies certified or otherwise proved to our satisfaction of the
following:

     (i)    the Certificate of Incorporation of the Company as filed with the
            Secretary of State of Delaware on March 2, 1990, as amended;

     (ii)   the Bylaws of the Company as of the date of this opinion;

     (iii)  the Amended and Restated Declaration of Trust (the "Declaration"),
            dated December 23, 1996, executed by the Company and by the trustees
            of the Trust;

     (iv)   the Registration Statement on Form S-3 (Registration No. 333-16231)
            of the Company, including the related prospectuses and prospectus
            supplements filed with the Securities and Exchange Commission 
            ("Registration Statement");

     (v)    the Indenture;

     (vi)   the Guarantee;

     (vii)  the Convertible Debentures; and

     (viii) such other documents, corporate records, certificates and other
            instruments as we have deemed necessary or appropriate for the
            purpose of this opinion.

     We have assumed the genuineness and authenticity of all signatures on all
original documents, the authenticity of all documents submitted to us as
originals, the conformity to originals of all documents submitted to us as
copies and the due authorization, execution, delivery or recordation of all
documents where due authorization, execution, delivery or recordation are
prerequisites to the effectiveness thereof.  Capitalized terms used herein and
not otherwise defined are used as defined in the Registration Statement.

     Based upon the foregoing, and having regard for such legal considerations
as we deem relevant, we are of the opinion that:

     (i)    The Company is a corporation duly organized, validly existing and in
            good standing under the laws of the State of Delaware pursuant to
            the Delaware General Corporation Law;

     (ii)   The Guarantee to be issued by the Company pursuant to the
            Registration Statement has been duly authorized for issuance, and
            when duly executed by the Company and delivered as contemplated in
            the Registration Statement, will be a legally issued and binding
            obligation of
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Nuevo Energy Company
1331 Lamar, Suite 1650
Houston, Texas 77010
Page 3

            the Company enforceable in accordance with its terms (except as
            limited by principles of equity or applicable bankruptcy,
            insolvency, reorganization, moratorium, or similar laws now or
            hereafter in effect affecting the rights of creditors generally);

     (iii)  The Convertible Debentures to be sold by the Company pursuant to the
            Registration Statement have been duly authorized for issuance, and
            when duly executed by the Company, authenticated by the Trustee and
            delivered and sold as contemplated the Registration Statement, will
            be legally issued and binding obligations of the Company enforceable
            in accordance with their terms and entitled to the benefits of the
            Indenture (except as limited by principles of equity or applicable
            bankruptcy, insolvency, reorganization, moratorium, or similar laws
            now or hereafter in effect affecting the rights of creditors
            generally);

     (iv)   The TECONS Shares to be sold by the Company will, upon issuance and
            delivery upon conversion of the Convertible Debentures as
            contemplated in the Registration Statement, be duly and validly
            authorized and legally issued, fully paid and nonassessable;

     (v)    The Outstanding Shares are duly and validly authorized and legally
            issued, fully paid and nonassessable; and

     (vi)   The Conversion Shares will, upon issuance and delivery upon
            conversion of the Preferred Stock, be duly and validly authorized
            and legally issued, fully paid and nonassessable.

     We hereby consent to the filing of this opinion as an Exhibit to the
Registration Statement and to the references to us under the caption "Legal
Matters" in the prospectuses and prospectus supplements forming a part of the
Registration Statement.


                              Very truly yours,



                              BUTLER & BINION, L.L.P.