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                                                                     Exhibit 5.1

                           OPINION OF BAKER & McKENZIE

                                December 23, 2002

Harken Energy Corporation
580 WestLake Park Boulevard
Suite 600
Houston, Texas 77079

Re: Registration Statement on Form S-3 (File No. 333-99579)

Ladies and Gentlemen:

     We have acted as counsel for Harken Energy Corporation, a Delaware
corporation (the "Company"), in connection with the registration statement on
Form S-3 filed with the Securities and Exchange Commission under the Securities
Act of 1933, as amended (the "Registration Statement"), with respect to a
maximum of 95,238,096 shares of the Company's common stock, par value $0.01 per
share (the "Shares"), to be issued by the Company in connection with the
Company's distribution to holders of its common stock, Series G1 preferred stock
and Series G2 preferred stock of nontransferable subscription rights to purchase
the Shares, as described in the Registration Statement (the "Rights Offering").

     In reaching the opinion set forth below, we have examined originals or
copies, certified or otherwise identified, of the Company's Certificate of
Incorporation, as amended, the Company's Bylaws, as amended, resolutions as
adopted by the Company's Board of Directors, and such documents, corporate
records and other instruments as we have deemed necessary or advisable for
purposes of this opinion. As to matters of fact, which have not been
independently established or verified, we have examined and relied upon such
corporate records and documents of the Company as we have deemed necessary or
appropriate to render this opinion and, where we have deemed appropriate,
statements, representations or certificates related to factual matters of
officers of the Company or public officials. We have assumed the authenticity of
all documents submitted to us as originals, the genuineness of all signatures,
the legal capacity of natural persons and the conformity to the originals of all
documents submitted to us as copies.

     Based on the foregoing and subject to the limitations, qualifications,
exceptions and assumptions set forth herein, we are of the opinion that the
Shares have been duly authorized and, when the Registration Statement has been
declared effective by order of the Securities and

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Exchange Commission and the Shares have been issued and paid for upon the terms
and conditions set forth in the Registration Statement and the Rights Offering,
the Shares will be validly issued, fully paid and non-assessable.

     The opinion expressed above is specifically limited to the General
Corporation Laws, as amended, of the State of Delaware and the federal laws of
the United States of America. The Shares may be issued on a delayed basis, but
this opinion is limited to the laws, including the rules and regulations
thereunder, as in effect on the date hereof.

     This opinion (i) is rendered in connection with the filing of the
Registration Statement, (ii) is rendered as of the date hereof, and we undertake
no, and hereby disclaim any kind of obligation to advise you of any change or
any new developments that might affect any matters or opinions set forth herein,
and (iii) is limited to the matters stated herein and no opinions may be
inferred or implied beyond the matters expressly stated herein.

     We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm's name under the heading
"Legal Matters." In giving this consent, this firm does not thereby admit that
it comes within the category of persons whose consent is required under Section
7 of the Securities Act of 1933, as amended, or the rules and regulations of the
Securities and Exchange Commission promulgated thereunder.

                                                Very truly yours,


                                                /s/ Baker & McKenzie
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