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                                                                     EXHIBIT 5.1

                                  June 23, 2000

Board of Directors
Basic Energy Services, Inc.
406 North Big Spring
Midland, Texas 79701

Gentlemen:

         We have acted as counsel to Basic Energy Services, Inc., a Delaware
corporation (the "Company"), in connection with 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-1
filed by the Company with the Commission on March 23, 2000, as amended on May
22, 2000 (the "Registration Statement"), with respect to the offering and sale
by the Company of up to 4,255,000 shares (the "Shares") of common stock, par
value $0.01 per share (the "Common Stock"), of the Company. This opinion also
relates to any registration statement of the Company relating to the
registration of additional shares of Common Stock pursuant to Rule 462(b) under
the Act.

         We have examined originals or copies of (i) the Amended and Restated
Certificate of Incorporation of the Company; (ii) the Restated Bylaws of the
Company; (iii) certain resolutions of the Board of Directors and the
stockholders of the Company; and (iv) such other documents and records as we
have deemed necessary and relevant for purposes hereof. We have relied upon
certificates of public officials and officers of the Company as to certain
matters of fact relating to this opinion and have made such investigations of
law as we have deemed necessary and relevant as a basis hereof. We have not
independently verified any factual matter relating to this opinion.

         We have assumed the genuineness of all signatures, the authenticity of
all documents, certificates and records submitted to us as copies, and the
conformity to original documents, certificates and records of all documents,
certificates and records submitted to us as copies.

         Based upon the foregoing, and subject to the limitations and
assumptions set forth herein, and having due regard for such legal
considerations as we deem relevant, we are of the opinion that:

         The issuance of the Common Stock has been duly authorized, and when
issued and delivered by the Company against payment therefor as described in the
Registration Statement, such shares will be validly issued, fully paid and
nonassessable.


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Basic Energy Services, Inc.
May 22, 2000
Page 2

         The foregoing opinion is based on and is limited to the General
Corporation Law of the State of Delaware and the relevant laws of the United
States of America, and we render no opinion with respect to the laws of any
other jurisdiction.

         We hereby consent to the filing of this opinion with the Securities and
Exchange Commission as Exhibit 5.l to the Registration Statement and to the
reference to this firm under the caption "Legal Matters" in the prospectus
contained in the Registration Statement. By giving such consent, we do not admit
that we are included within the category of persons whose consent is required
under Section 7 of the Securities Act or the rules and regulations issued
thereunder. This opinion may be incorporated by reference in a registration
statement of the Company relating to the registration of additional shares of
Common Stock pursuant to Rule 462(b) under the Securities Act, in which case the
opinions expressed herein will apply to the additional shares registered
thereunder.

                           Very truly yours,


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







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