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                                                                    EXHIBIT 5.1

                               September 28, 1999

Callon Petroleum Company
200 North Canal St.
Natchez, MS 39120

Ladies and Gentlemen:

We have acted as counsel to Callon Petroleum Company, a Delaware corporation
(the "Company"), in connection with the preparation for filing with the
Securities and Exchange Commission of a Registration Statement (the
"Registration Statement") under the Securities Act of 1933, as amended (the
"Act"). The Registration Statement relates to (i) debt securities of the
Company ("Debt Securities"), (ii) shares of preferred stock, par value $0.01
per share, of the Company ("Preferred Stock"), (iii) shares of common stock,
par value $0.01 per share, of the Company ("Common Stock"), (iv) warrants to
purchase other securities ("Warrants"), and (v) securities purchase contracts
to purchase Common Stock or Preferred Stock ("Securities Purchase Contracts"
and, together with the Debt Securities, the Preferred Stock, the Common Stock
and the Warrants, the "Securities") that may be issued and sold by the Company
from time to time pursuant to Rule 415 under the Act for an aggregate initial
offering price not to exceed $125,000,000. In connection with the Registration
Statement certain legal matters in connection with the Securities are being
passed upon for you by us.

In our capacity as your counsel in the connection referred to above, we have
examined (i) the Certificate of Incorporation and Bylaws of the Company, each
as amended to date (together, the "Charter Documents"), (ii) the form of
indenture filed as Exhibit 4.11 to the Registration Statement to be executed by
the Company and the trustee thereunder (the "Senior Debt Indenture") pursuant
to which senior Debt Securities may be issued, (iii) the form of indenture
filed as Exhibit 4.12 to the Registration Statement to be executed by the
Company and the trustee thereunder (the "Subordinated Debt Indenture" and,
together with the Senior Debt indenture, the "Indentures") pursuant to which
subordinated Debt Securities may be issued, and (iv) the originals, or copies
certified or otherwise identified, of corporate records of the Company,
certificates of public officials and of representatives of the Company,
statutes and other instruments and documents as a basis for the opinions
hereafter expressed.

In connection with this opinion, we have assumed that (i) the Registration
Statement, and any amendments thereto (including post-effective amendments),
will have become effective; (ii) a Prospectus Supplement will have been
prepared and filed with the Commission describing the Securities offered
thereby; (iii) all Securities will be issued and sold in compliance with
applicable federal and state securities laws and in the manner stated in the
Registration Statement and the appropriate Prospectus Supplement; (iv) a
definitive purchase, underwriting or similar agreement with respect to any
Securities offered will have been duly authorized and validly executed and
delivered by the Company and the other parties thereto; (v) any securities
issuable upon conversion,


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exchange, redemption or exercise of any Securities being offered will be duly
authorized, created and, if appropriate, reserved for issuance upon such
conversion, exchange, redemption or exercise and (vi) with respect to shares of
Common Stock or Preferred Stock offered, there will be sufficient shares of
Common Stock or Preferred Stock authorized under the Company's Charter
Documents and not otherwise reserved for issuance.

Based upon and subject to the foregoing, we are of the opinion that:

1.   With respect to shares of Common Stock, when (i) the Board of Directors of
     the Company or, to the extent permitted by the General Corporation Law of
     the State of Delaware and the Company's Charter Documents, a duly
     constituted and acting committee thereof (such Board of Directors or
     committee being hereinafter referred to as the "Board") has taken all
     necessary corporate action to approve the issuance thereof and the terms
     of the offering of shares of Common Stock and related matters, and (ii)
     certificates representing the shares of Common Stock have been duly
     executed, countersigned, registered and delivered either (a) in accordance
     with the applicable definitive purchase, underwriting or similar agreement
     approved by the Board upon payment of the consideration therefor (not less
     than the par value of the Common Stock) provided for therein, or (b) upon
     conversion, exchange, redemption or exercise of any other Security, in
     accordance with the terms of such Security or the instrument governing
     such Security providing for such conversion, exchange, redemption or
     exercise as approved by the Board, for the consideration approved by the
     Board (not less than the par value of the Common Stock), the shares of
     Common Stock will be duly authorized, validly issued, fully paid and
     non-assessable.

2.   With respect to shares of Preferred Stock, when (i) the Board has taken
     all necessary corporate action to approve and establish the terms of the
     shares of Preferred Stock, to approve the issuance thereof and the terms
     of the offering thereof and related matters, including the adoption of a
     Certificate of Designations relating to such Preferred Stock (a
     "Certificate of Designations"), and such Certificate of Designations has
     been filed with the Secretary of State of the State of Delaware, and (ii)
     certificates representing the shares of Preferred Stock have been duly
     executed, countersigned, registered and delivered either (a) in accordance
     with the applicable definitive purchase, underwriting or similar agreement
     approved by the Board upon payment of the consideration therefor (not less
     than the par value of the Preferred Stock) provided for therein, or (b)
     upon conversion, exchange, redemption or exercise of any other Security,
     in accordance with the terms of such Security or the instrument governing
     such Security providing for such conversion, exchange, redemption or
     exercise as approved by the Board, for the consideration approved by the
     Board (not less than the par value of the Preferred Stock), the shares of
     Preferred Stock will be duly authorized, validly issued, fully paid and
     non-assessable.

3.   With respect to Debt Securities to be issued under the Senior Debt
     Indenture, when (i) the Senior Debt Indenture has been duly authorized and
     validly executed and delivered by the Company to the trustee, (ii) the
     Senior Debt Indenture has been duly qualified

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     under the Trust Indenture Act of 1939, as amended, (iii) the Board has
     taken all necessary corporate action to approve and establish the terms of
     such Debt Securities, to approve the issuance thereof and the terms of the
     offering thereof and related matters, and (iv) such Debt Securities have
     been duly executed, authenticated, issued and delivered in accordance with
     both the provisions of the Senior Debt Indenture and either (a) the
     provisions of the applicable definitive purchase, underwriting or similar
     agreement approved by the Board upon payment of the consideration therefor
     provided for therein or (b) upon conversion, exchange, redemption or
     exercise of any other Security, in accordance with the terms of such
     Security or the instrument governing such Security providing for such
     conversion, exchange, redemption or exercise as approved by the Board, for
     the consideration approved by the Board, such Debt Securities will
     constitute legal, valid and binding obligations of the Company.

4.   With respect to Debt Securities to be issued under the Subordinated Debt
     Indenture, when (i) the Subordinated Debt Indenture has been duly
     authorized and validly executed and delivered by the Company to the
     trustee, (ii) the Subordinated Debt Indenture has been duly qualified
     under the Trust Indenture Act of 1939, as amended, (iii) the Board has
     taken all necessary corporate action to approve and establish the terms of
     such Debt Securities, to approve the issuance thereof and the terms of the
     offering thereof and related matters, and (iv) such Debt Securities have
     been duly executed, authenticated, issued and delivered in accordance with
     both the provisions of the Subordinated Debt Indenture and either (a) the
     provisions of the applicable definitive purchase, underwriting or similar
     agreement approved by the Board upon payment of the consideration therefor
     provided for therein or (b) upon conversion, exchange, redemption or
     exercise of any other Security, in accordance with the terms of such
     Security or the instrument governing such Security providing for such
     conversion, exchange, redemption or exercise as approved by the Board, for
     the consideration approved by the Board, such Debt Securities will
     constitute legal, valid and binding obligations of the Company.

5.   With respect to Warrants, when (i) the Board has taken all necessary
     corporate action to approve the creation of and the issuance and terms of
     the Warrants, the terms of the offering thereof and related matters, (ii)
     the Warrant Agreement or Agreements relating to the Warrants have been
     duly authorized and validly executed and delivered by the Company and the
     Warrant Agent appointed by the Company, and (iii) the Warrants or
     certificates representing the Warrants have been duly executed,
     countersigned, registered and delivered in accordance with the appropriate
     Warrant Agreement or Agreements and the applicable definitive purchase,
     underwriting or similar agreement approved by the Board upon payment of
     the consideration therefor provided for therein, the Warrants will be duly
     authorized and validly issued and will constitute legal, valid and binding
     obligations of the Company.


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6.   With respect to Securities Purchase Contracts, when (i) the Board has
     taken all necessary corporate action to approve the creation of and the
     issuance and terms of the Securities Purchase Agreements, the terms of the
     offering thereof and related matters, (ii) the Purchase Contract Agreement
     or Agreements relating to the Securities Purchase Contracts have been duly
     authorized and validly executed and delivered by the Company, and (iii)
     the Securities Purchase Contracts have been duly executed, countersigned,
     registered and delivered in accordance with the appropriate Purchase
     Contract Agreement or Agreements and the applicable definitive purchase,
     underwriting or similar agreement approved by the Board upon payment of
     the consideration therefor provided for therein, the Securities Purchase
     Contracts will be duly authorized and validly issued and will constitute
     legal, valid and binding obligations of the Company.

Our opinions set forth above are subject to the effect of (a) applicable
bankruptcy, reorganization, insolvency, moratorium and other similar laws and
court decisions of general application (including without limitation statutory
or other laws regarding fraudulent or preferential transfers) relating to,
limiting or affecting the enforcement of creditors' rights generally, (b)
general principles of equity that may limit the enforceability of any of the
remedies, covenants or other provisions of the Debt Securities, the Indentures,
the Warrants, the Warrant Agreements, the Securities Purchase Contracts, the
Purchase Contract Agreements and the Certificate of Designations and the
availability of injunctive relief or other equitable remedies and (c) the
application of principles of equity (regardless of whether enforcement is
considered in proceedings at law or in equity) as such principles relate to,
limit or affect the enforcement of creditors' rights generally.

In addition, we express no opinion as to: (a) any provisions of the Debt
Securities, the Indentures, the Warrant Agreements, the Warrants, the
Securities Purchase Contracts, the Purchase Contract Agreements or the
Certificate of Designations regarding the remedies available to any person (1)
to take action that is arbitrary, unreasonable or capricious or is not taken in
good faith or in a commercially reasonable manner, whether or not such action
is permitted under the Debt Securities, the Indentures, the Warrant Agreements,
the Warrants, the Securities Purchase Contracts, the Purchase Contract
Agreements or the Certificate of Designations or (2) for violations or breaches
that are determined by a court to be non-material or without substantially
adverse effect upon the ability of the Company to perform its material
obligations under the Debt Securities, the Indentures, the Warrant Agreements,
the Warrants, the Securities Purchase Contracts, the Purchase Contract
Agreements or the Certificate of Designations; or (b) the provisions of the
Debt Securities or the Indentures that may provide for interest on interest or
penalty interest.

To the extent that the obligations of the Company under any Warrant Agreement
may be dependent upon such matters, we assume for purposes of this opinion that
the applicable Warrant Agent is duly organized, validly existing and in good
standing under the laws of its jurisdiction of organization; that the Warrant
Agent is duly qualified to engage in the activities

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contemplated by the Warrant Agreement; that the Warrant Agreement has been duly
authorized, executed and delivered by the Warrant Agent and constitutes the
valid and binding obligation of the Warrant Agent enforceable against the
Warrant Agent in accordance with its terms; that the Warrant Agent is in
compliance, with respect to acting as a Warrant Agent under the Warrant
Agreement, with all applicable laws and regulations; and that the Warrant Agent
has the requisite organizational and legal power and authority to perform its
obligations under the Warrant Agreement.

To the extent that the obligations of the Company under any Indenture may be
dependent upon such matters, we assume for purposes of this opinion that the
Trustee is duly organized, validly existing and in good standing under the laws
of its jurisdiction of organization; that the Trustee is duly qualified to
engage in the activities contemplated by such Indenture; that such Indenture
has been duly authorized, executed and delivered by the Trustee and constitutes
the valid and binding obligation of the Trustee enforceable against the Trustee
in accordance with its terms; that the Trustee is in compliance, with respect
to acting as a trustee under such Indenture, with all applicable laws and
regulations; and that the Trustee has the requisite organizational and legal
power and authority to perform its obligations under such Indenture.

The foregoing opinions are limited to the laws of the United States of America
and to the General Corporation Law of the State of Delaware.

This opinion letter has been prepared for your use in connection with the
Registration Statement and speaks as of the date hereof. We assume no
obligation to advise you of any changes in the foregoing subsequent to the
delivery of this opinion letter.

We hereby consent to the filing of this opinion of counsel as Exhibit 5.1 to
the Registration Statement. We also consent to the reference to our Firm under
the heading "Legal Matters" in the Prospectus forming a part of the
Registration Statement. In giving this consent, we do not hereby admit that we
are in the category of persons whose consent is required under Section 7 of the
Act.

Very truly yours,



/s/ HAYNES AND BOONE, LLP