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                                                                     Exhibit 5.1

                                  Law Offices
                                 McAfee & Taft
                          A Professional Corporation
                       10th Floor, Two Leadership Square
                              211 North Robinson
                      Oklahoma City, Oklahoma 73102-7103
                                (405) 235-9621
                              Fax (405) 235-0439
                           http://www.mcafeetaft.com



                               December 15, 2000


Devon Energy Corporation
20 North Broadway, Suite 1500
Oklahoma City, Oklahoma  73102-8260

Ladies and Gentlemen:

          Reference is made to your Registration Statement on Form S-3 filed
with the Securities and Exchange Commission (the "Commission") on November 16,
2000 relating to the proposed issuance and sale from time to time of up to
$447,261,200 aggregate initial offering price of (a) shares of common stock, par
value $0.10 per share (the "Common Stock") of Devon Energy Corporation, a
Delaware corporation (the "Company"), (b) shares of preferred stock, par value
$1.00 per share of the Company (the "Preferred Stock"), (c) the Company's debt
securities (the "Debt Securities"), (d) the Company's stock purchase contracts
(the "Stock Purchase Contracts"), (e) the Company's stock purchase units (the
"Stock Purchase Units"), consisting of stock purchase contracts and other
securities, (f) preferred securities (the "Trust Preferred Securities") of Devon
Financing Trust II (the "Trust"), and (g) the Company's guarantee with respect
to the Trust Preferred Securities (each, a "guarantee" and collectively, the
"Guarantees"). The Common Stock, the Preferred Stock, the Debt Securities, the
Stock Purchase Contracts, the Stock Purchase Units, the Trust Preferred
Securities and the Guarantees may hereinafter be referred to as the
"Securities." The Debt Securities will be issued pursuant to an indenture to be
entered into between the Company and the Bank of New York, in the form filed as
an exhibit to the Registration Statement, as such indenture may be supplemented
(the "Indenture"). Each Stock Purchase Contract will be issued pursuant to an
agreement (the "Purchase Agreement"). Each Guarantee will be issued pursuant to
a guarantee agreement to be entered into between the Company and the Bank of New
York, as guarantee trustee thereunder in the form filed as an exhibit to the
Registration Statement, as supplemented (each, a "Guarantee Agreement" and,
collectively, the "Guarantee Agreements").

          We have examined the corporate records of the Company, have attended
meetings of the Company's board of directors and have made such other
investigations as we have deemed appropriate in order to express the opinions
set forth herein. We have reviewed the formation documents of the Trust. We have
also examined a copy of the Registration Statement and originals or copies,
certified or otherwise identified to our satisfaction, of such documents,
corporate records, certificates of public officials and other instruments and
matters of law as we have deemed necessary for purposes of rendering opinions
hereinafter expressed.
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          In our examinations, we have assumed the genuineness of all
signatures, the authenticity of all documents submitted to us as originals and
the conformity with the originals of all documents submitted to us as copies.

          In connection with this opinion, we have assumed (a) the Registration
Statement, and any amendments thereto (including pre- and post-effective
amendments), will become effective under the Securities Act; (b) a prospectus
supplement will be filed with the Commission describing the Securities offered
thereby; (c) 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 applicable prospectus supplement; (d) 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; (e) any Securities
issuable upon conversion, 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; (f) 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 Certificate of Incorporation at the time and not otherwise reserved
for issuance, and the consideration received will be at least equal to the par
value thereof; and (g) each of the agreements in question to which the Company
or the Trust is a party is enforceable against the other parties thereto.

          Based on such examination and review and subject to the qualifications
set forth herein, we are of the opinion that:

          1.   The Company is a corporation duly incorporated and validly
existing in good standing under the laws of the State of Delaware.

          2.   The shares of Common Stock will be duly authorized, validly
issued, fully paid and non-assessable, when (a) the Board of Directors of the
Company or, to the extent permitted by the General Corporation Law of the State
of Delaware and Certificate of Incorporation and Bylaws (the "charter
documents") of the Company, 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 final financial and other terms of the offering of shares of
Common Stock and related matters, and (b) certificates representing the shares
of Common Stock have been duly executed, countersigned, registered and
delivered, or if uncertificated, valid book-entry notations are made in the
share register of the Company, either (i) in accordance with the applicable
definitive purchase, underwriting or similar agreement approved by the Board in
exchange for payment of the consideration therefor provided for therein, or (ii)
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.

          3.   The shares of Preferred Stock will be duly authorized, validly
issued, fully paid and non-assessable, when (a) the Board has taken all
necessary corporate action to approve and establish the final financial and
other 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
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of a Certificate of Designation relating to such Preferred Stock (a "Certificate
of Designation"), and such Certificate of Designation has been filed with the
Secretary of State of the State of Delaware, and (b) certificates representing
the shares of Preferred Stock have been duly executed, countersigned, registered
and delivered, or if uncertificated, valid book-entry notations are made in the
share register of the Company, either (i) in accordance with the applicable
definitive purchase, underwriting or similar agreement approved by the Board in
exchange for payment of the consideration therefor provided for therein, or (ii)
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.

          4.   The Debt Securities will constitute legal, valid and binding
obligations of the Company, enforceable against the Company in accordance with
their terms, when (a) the Indenture relating to such Securities and a supplement
establishing the specific terms of such securities have been duly authorized and
validly executed and delivered by each of the parties thereto, (b) the Board has
taken all necessary corporate action to approve and establish the terms of such
series and to authorize and approve the issuance thereof, the terms of the
offering thereof and related matters, and (c) the Debt Securities of such series
have been executed, authenticated, issued and delivered in accordance with the
Indenture, any applicable supplemental indenture relating to such series and the
applicable definitive purchase, underwriting or similar agreement approved by
the Board, in exchange for payment of the consideration therefor provided for
therein.

          5.   The Stock Purchase Contracts will constitute legal, valid and
binding obligations of the Company, enforceable against the Company in
accordance with their terms, when (a) each Purchase Agreement has been duly
authorized and validly executed and delivered by each of the parties thereto,
(b) the Board has taken all necessary corporate action to approve and establish
the terms of such Stock Purchase Contracts and to authorize and approve the
issuance thereof, the terms of the offering thereof and related matters, and (c)
the Stock Purchase Contracts have been duly executed and delivered in accordance
with the Purchase Agreements and the applicable definitive purchase,
underwriting or similar agreement approved by the Board in exchange for payment
of the consideration therefor provided for therein.

          6.   The Trust has been duly created and is validly existing in good
standing as a business trust under the Delaware Business Trust Act.

          7.   With respect to the Trust Preferred Securities, when (a) an
Amended and Restated Declaration of Trust between the Company and the trustees
named therein, in the form filed as an exhibit to the Registration Statement,
and any amendment or supplement specifying the final financial and other terms
of the Trust Preferred Securities (the "Trust Agreement") have been duly
authorized and validly executed and delivered by each of the parties thereto,
(b) the trustees and the Board have taken all necessary action to authorize and
approve the issuance of the Trust Preferred Securities, (c) certificates
representing the Trust Preferred Securities have been duly executed,
countersigned, registered and delivered in accordance with the applicable
definitive purchase, underwriting or similar agreement approved by the Company
and the trustees in exchange for payment of the consideration therefor, and (d)
the Trust Preferred Securities are issued in accordance with the Trust
Agreement, the Trust Preferred Securities will
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represent valid and, subject to the qualifications set forth in paragraph 8
below, fully paid and non-assessable beneficial interests in the assets of the
trust.

          8.   Holders of the Trust Preferred Securities, as beneficial owners
of the Trust, will be entitled to the same limitation of personal liability
extended to stockholders of private corporations for profit organized under the
General Corporation Law of the State of Delaware, and will not be required to
make any additional payments or take any other action except as otherwise
described in the Registration Statement, the prospectus and any prospectus
supplement.

          9.   With respect to each Guarantee Agreement, when (a) such Guarantee
Agreement in the form filed as an exhibit to the Registration Statement, and any
amendments or supplements specifying the final terms thereof, have been duly
authorized, validly executed and delivered by each of the parties thereto, and
(b) the Board has taken all necessary corporate action to approve the Guarantee
and issuance thereof and related matters, such Guarantee Agreement will
constitute the legal, valid and binding obligation of the Company, enforceable
against the Company in accordance with its terms.

          Our opinions expressed above are subject to the qualifications that we
express no opinions as to the applicability of, compliance with, or effect of
(i) any bankruptcy, insolvency, reorganization, fraudulent transfer, fraudulent
conveyance, moratorium or other similar law affecting the enforcement of
creditor's rights generally, (ii) general principles of equity (regardless of
whether enforcement is considered in a proceeding in equity or at law), and
(iii) public policy considerations which may limit the rights of parties to
obtain certain remedies.

          We are members of the Bar of the State of Oklahoma and the foregoing
opinion is limited to the laws of the State of Oklahoma, the federal laws of the
United States of America, the General Corporation Law of the State of Delaware
and the Delaware Business Trust Act.

          We hereby consent to the filing of this opinion letter as an exhibit
to the Registration Statement. We also consent to the reference to our name
under the caption "Legal Matters" in the prospectus contained in the
Registration Statement. In giving this consent, we do not hereby admit that we
are the category of persons whose consent is required under Section 7 of the Act
or the rules and regulations of the Commission.

                               Very truly yours,