EXHIBIT 5.1


                                                       VINSON & ELKINS L.L.P.
                                                       2300 FIRST CITY TOWER
                                                       1001 FANNIN STREET
[VINSON & ELKINS LETTERHEAD]                           HOUSTON, TEXAS 77002-6760
                                                       TELEPHONE (713) 758-2222
                                                       FAX (713) 758-2346

                                                       www.velaw.com



                                October 31, 2002



Ocean Energy, Inc.
1001 Fannin St., Suite 1600
Houston, Texas 77002

Ladies and Gentlemen:

         We have acted as counsel for Ocean Energy, Inc., a Delaware corporation
(the "Company"), with respect to certain legal matters in connection with the
registration by the Company under the Securities Act of 1933, as amended (the
"Securities Act"), of the offer and sale of 8,842,351 shares of common stock,
par value $.10 per share, of the Company (the "Shares") pursuant to the Ocean
Energy, Inc. Long-Term Incentive Plan for Nonexecutive Employees (the "Plan").

         In connection with the foregoing, we have examined or are familiar with
the Certificate of Incorporation of the Company, as amended, the Restated Bylaws
of the Company, the corporate proceedings with respect to the issuance of the
Shares, the registration statement on Form S-8 filed in connection with the
registration of the Shares (the "Registration Statement"), and such other
certificates, instruments and documents as we have considered necessary or
appropriate for purposes of this opinion.

         Based upon the foregoing, we are of the opinion that the Shares have
been duly authorized and, when the Shares are issued in accordance with the
provisions of the Plan, will be validly issued and fully paid and
non-assessable.

         The foregoing opinion is limited to the laws of the United States of
America, the Constitution of the State of Delaware and the General Corporation
Law of the State of Delaware, as interpreted by federal courts and the courts of
the State of Delaware.

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement. In giving this consent, we do not admit that we are
within the category of persons whose consent is required under Section 7 of the
Securities Act and the rules and regulations thereunder.


                                              Very truly yours,


                                              /s/ Vinson & Elkins L.L.P.



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