Exhibit 5

May 2, 2008

Newfield Exploration Company
363 N. Sam Houston Parkway E., Suite 2020
Houston, Texas 77060

     Re: Registration Statement on Form S-3 filed on May 2, 2008

Ladies and Gentlemen:

     We acted as counsel to Newfield Exploration Company (the “Company”) in connection with the above-referenced Registration Statement on Form S-3 (the “Registration Statement”) filed with the Securities and Exchange Commission (the “SEC”) under the Securities Act of 1933, as amended (the “Act”), relating to the proposed public offering of an indeterminate amount of (i) unsecured debt securities of the Company (“Debt Securities”), in one or more series, which may be either senior or subordinated in priority of payment and certain of which may be convertible into or exchangeable for common stock, par value $0.01, of the Company (including attached preferred share purchase rights, “Common Stock”); (ii) shares of its Common Stock; and (iii) shares of preferred stock, $0.01 par value, of the Company, in one or more series (the “Preferred Stock” and, together with the Debt Securities and the Common Stock, the “Securities”). The Securities may be sold by the Company from time to time as set forth in the Registration Statement, the prospectus which forms a part of the Registration Statement (the “Prospectus”), and as to be set forth in one or more supplements to the Prospectus (each, a “Prospectus Supplement”).

     We have examined originals or copies, certified or otherwise identified to our satisfaction, of (a) the Second Restated Certificate of Incorporation and Bylaws of the Company, each as amended to the date hereof, (b) resolutions adopted by the Board of Directors of the Company (the Board of Directors, or to the extent permitted by Section 141 of the Delaware General Corporation Law (the “DGCL”), a duly constituted and acting committee thereof, being referred to herein as the “Board”), (c) the Registration Statement, (d) the Senior Indenture dated as of February 28, 2001 (the “Senior Indenture”) between the Company and U.S. Bank National Association (as successor to Wachovia Bank, National Association (formerly First Union National Bank)), as Trustee, (e) the Subordinated Indenture dated as of December 10, 2001 (the “Subordinated Indenture”) between the Company and U.S. Bank National Association (as

successor to Wachovia Bank, National Association (formerly First Union National Bank)), as Trustee, and (f) such other certificates, statutes and other instruments and documents as we considered appropriate for purposes of the opinions hereafter expressed. In addition, we reviewed such questions of law as we considered appropriate.

     As to any facts material to the opinions contained herein, we made no independent investigation of such facts and have relied, to the extent that we deem such reliance proper, upon certificates of public officials and officers or other representatives of the Company.

     In connection with rendering the opinions set forth below, we assumed that (a) all information contained in all documents reviewed by us is true and correct; (b) all signatures on all documents examined by us are genuine; (c) all documents submitted to us as originals are authentic and all documents submitted to us as copies conform to the originals of those documents; (d) each natural person signing any document reviewed by us had the legal capacity to do so; (e) each person signing in a representative capacity (other than on behalf of the Company) any document reviewed by us had authority to sign in such capacity; (f) one or more prospectus supplements to the prospectus contained in the Registration Statement will have been prepared and filed with the Commission describing the Securities offered thereby; (g) 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 an applicable prospectus supplement; (h) any supplemental indenture relating to a series of Debt Securities to be issued under the Senior Indenture or the Subordinated Indenture will be duly authorized, executed and delivered by the parties thereto in substantially the form reviewed by us; (i) at the time of any offering or sale of any shares of Common Stock or Preferred Stock, that the Company will have at least such number of shares of Common Stock or Preferred Stock authorized, established (if applicable) and available for issuance; (j) 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; and (k) any Securities issuable upon conversion, exchange or exercise of any Securities being offered will have been duly authorized, established (if appropriate) and reserved for issuance upon such conversion, exchange or exercise.

     Based on the foregoing, and subject to the assumptions, qualifications, limitations and exceptions set forth herein, we are of the opinion that:

(a) With respect to Debt Securities to be issued under the Senior Indenture, when (i) the Board has taken all necessary corporate action to approve the issuance and terms of such Debt Securities, the terms of the offering thereof and related matters; (ii) the terms of such Debt Securities and of their issuance and sale have been established so as not to violate any applicable law or result in a default under or breach of any agreement or instrument binding upon the Company and so as to comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company; and (iii) such Debt Securities have been duly executed, authenticated, issued and delivered in accordance

	with the provisions of the Senior Indenture and in accordance with the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration provided for therein, such Debt Securities will be legally issued and will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their terms and will be entitled to the benefits of the Senior Indenture.
(b)	With respect to Debt Securities to be issued under the Subordinated Indenture, when (i) the Board has taken all necessary corporate action to approve the issuance and terms of such Debt Securities, the terms of the offering thereof and related matters; (ii) the terms of such Debt Securities and of their issuance and sale have been established so as not to violate any applicable law or result in a default under or breach of any agreement or instrument binding upon the Company and so as to comply with any requirement or restriction imposed by any court or governmental body having jurisdiction over the Company; and (iii) such Debt Securities have been duly executed, authenticated, issued and delivered in accordance with the provisions of the Subordinated Indenture and in accordance with the applicable definitive purchase, underwriting or similar agreement approved by the Board upon payment of the consideration provided for therein, such Debt Securities will be legally issued and will constitute valid and binding obligations of the Company, enforceable against the Company in accordance with their terms and will be entitled to the benefits of the Subordinated Indenture.
(c)	With respect to shares of Common Stock, when (i) the Board has taken all necessary corporate action to approve the issuance and terms of the offering thereof 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 (not less than the par value of the Common Stock) provided for therein; or (B) upon conversion, exchange or exercise of any other Security in accordance with the terms of the Security or the instrument governing the Security providing for the conversion, exchange or exercise as approved by the Board, for the consideration approved by the Board (not less than the par value of the Common Stock), such shares of Common Stock will be validly issued, fully paid and non-assessable.
(d)	With respect to shares of any series of Preferred Stock, when (i) the Board has taken all necessary corporate action to approve the issuance and terms of the shares of the series, the terms of the offering thereof and related matters, including the adoption of a resolution establishing and designating the series and fixing and determining the preferences, limitations and relative rights thereof and the filing of a statement with

respect to the series with the Secretary of State of the State of Delaware as required under Section 151 of the DGCL (the “Certificate of Designation”); and (ii) certificates representing the shares of the series 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 (not less than the par value of the Preferred Stock) provided for therein; or (B) upon conversion, exchange or exercise of any other Security in accordance with the terms of the Security or the instrument governing the Security providing for the conversion, exchange 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 the series of Preferred Stock will be validly issued, fully paid and non-assessable.

     The foregoing opinions are qualified to the extent that the enforceability of any document, instrument or Security may be limited by or subject to (a) bankruptcy, insolvency, fraudulent transfer or conveyance, reorganization, moratorium or other similar laws relating to or affecting creditors’ rights generally, and general equitable or public policy principles; and (b) with respect to any Debt Securities denominated in a currency other than United States dollars, the requirement that a claim (or a foreign currency judgment in respect of such a claim) with respect to such Securities be converted to United States dollars at a rate of exchange prevailing on a date determined pursuant to applicable law or governmental authority.

     We express no opinions concerning (a) the validity or enforceability of any provisions contained in the Senior Indenture or the Subordinated Indenture that purport to waive or not give effect to rights to notices, defenses, subrogation or other rights or benefits that cannot be effectively waived under applicable law; or (b) the enforceability of indemnification provisions to the extent they purport to relate to liabilities resulting from or based upon negligence or any violation of federal or state securities or blue sky laws.

     We express no opinion as to the applicability of, compliance with or effect of, the law of any jurisdiction other than United States federal law, the laws of the State of New York and, to the extent relevant to the opinions expressed herein, the DGCL and applicable provisions of the Delaware Constitution, in each case as currently in effect, and reported judicial decisions interpreting the DGCL and such provisions of the Delaware Constitution.

     We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the use of our name in each prospectus forming a part of the Registration Statement under the caption “Legal Matters.” In giving this consent, we do not admit that we are within the category of persons whose consent is required under Section 7 of the Securities Act and the rules and regulations thereunder.

Very truly yours,
 

/s/ McDermott Will & Emery LLP