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                                                                     EXHIBIT 5.1

                      [LINDOW & TREAT, L.L.P. LETTERHEAD]


                                 April 17, 2001



Venus Exploration, Inc.
1250 N.E. Loop 410, Suite 1000
San Antonio, Texas 78209


Gentlemen:

         We have acted as special counsel to Venus Exploration Inc., a Delaware
corporation (the "Company"), in connection with the preparation of the
Registration Statement on Form S-8 (the "Registration Statement") filed with the
Securities and Exchange Commission under the Securities Act of 1933, as amended,
relating to the registration of 500,000 shares of Common Stock, par value $0.01
per share (the "Common Stock"), of the Company that may be issued pursuant to
the 1997 Incentive Plan of Venus Exploration, Inc., as amended (the "Plan"). The
law covered by the opinions expressed herein is limited to the federal law of
the United States and the General Corporation Law of the State of Delaware.

         In connection therewith, we have examined (i) the Certificate of
Incorporation and the Bylaws of the Company; (ii) minutes and records of the
corporate proceedings of the Company with respect to the adoption of the Plan
and the granting of awards thereunder; and (iii) such other documents as we have
deemed necessary for the expression of the opinion contained herein.

         In making the foregoing examination, we have assumed the genuineness of
all signatures and the authenticity of all documents submitted to us as
originals, and the conformity to original documents of all documents submitted
to us as certified or photostatic copies. Furthermore, we have assumed that the
exercise prices of all stock options that may be granted under the Plan will
equal or exceed the par value per share of the Common Stock. As to questions of
fact material to this opinion, where such facts have not been independently
established, and as to the content and form of the Certificate of Incorporation,
Bylaws, minutes, records, resolutions and other documents or writings of the
Company, we have relied, to the extent we deem reasonably appropriate, upon
representations or certificates of officers or directors of the Company and upon
documents, records and instruments furnished to us by the Company, without
independent check or verification of their accuracy.

         Based upon the foregoing, and having due regard for such legal
consideration as we deem relevant, we are of the opinion that the 500,000 shares
of Common Stock covered by the Registration Statement that may be issued from
time to time in accordance with the terms of the Plan have been duly authorized
for issuance by the Company and, when so issued in accordance with the terms and
conditions of the Plan and any related option or other applicable agreements,
will be validly issued, fully paid and nonassessable.

         We hereby consent to the filing of this opinion with the Securities and
Exchange Commission as an exhibit to the Registration Statement and to the
reference to our firm under the caption, "Item 5. Interests of Named Experts and
Counsel" in the Registration Statement.


                                              Sincerely yours,

                                              LINDOW & TREAT, LLP