Exhibit 5.1

May 4, 2017

Goodrich Petroleum Corporation

801 Louisiana, Suite 700

Houston, Texas 77002

Re: Registration Statement on Form S-3

Ladies and Gentlemen:

We have acted as counsel for Goodrich Petroleum Corporation, a Delaware corporation (the “Company”), with respect to certain legal matters in connection with the preparation and filing of a registration statement on Form S-3 (the “Registration Statement”) by the Company under the Securities Act of 1933, as amended (the “Securities Act”), related to the offer and sale by the Company from time to time, pursuant to Rule 415 under the Securities Act, of (i) debt securities of the Company, which may be either senior or subordinated and may be issued in one or more series, consisting of notes, debentures or other evidences of indebtedness (the “Debt Securities”) and which may be fully and unconditionally guaranteed (the “Guarantee”) by the Company’s subsidiary listed as co-registrant in the referenced Registration Statement (the “Subsidiary Guarantor”), (ii) shares of preferred stock, par value $1.00 per share, of the Company, in one or more series (the “Preferred Stock”), which may be issued in the form of depositary shares evidenced by depositary receipts (the “Depositary Shares”), (iii) shares of common stock, par value $0.01 per share, of the Company (the “Common Stock”) and (iv) warrants for the purchase of Common Stock, Preferred Stock and Debt Securities (the “Warrants” and, together with the Debt Securities, the Guarantee, the Preferred Stock, the Depositary Shares and the Common Stock, the “Securities”). The aggregate initial offering prices of the Securities to be offered and sold by the Company pursuant to the Registration Statement will not exceed $250,000,000.

We have also participated in the preparation of the Prospectus (the “Prospectus”) contained in the Registration Statement to which this opinion is an exhibit. The Securities will be offered in amounts, at prices and on terms to be determined in light of market conditions at the time of sale and to be set forth in supplements (each a “Prospectus Supplement”) to the Prospectus.

Vinson & Elkins LLP Attorneys at Law Austin  Beijing   Dallas   Dubai   Hong   Kong   Houston   London   Moscow   New York Palo Alto Richmond Riyadh San Francisco Taipei Tokyo Washington 1001 Fannin Street, Suite 2500 Houston, TX 77002-6760 Tel +1.713.758.2222 Fax +1.713.758.2346 www.velaw.com

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We have examined originals or copies, certified or otherwise identified to our satisfaction, of (i) the Certificate of Incorporation and Bylaws of the Company, each as amended to the date hereof, (ii) the Registration Statement, (iii) the form of Senior Indenture (the “Senior Indenture”), (iv) the form of Subordinated Indenture (the “Subordinated Indenture” and, together with the Senior Indenture, the “Indentures”), (v) resolutions of the board of directors of the Company and (vi) such other certificates, statutes and other instruments and documents as we considered appropriate for purposes of the opinions hereafter expressed. We have also reviewed such questions of law as we have deemed necessary or appropriate. As to matters of fact relevant to the opinions expressed herein, and as to factual matters arising in connection with our examination of corporate documents, records and other documents and writings, we relied upon certificates and other communications of corporate officers of the Company, without further investigation as to the facts set forth therein.

In connection with rendering the opinions set forth below, we have assumed that (i) all signatures on all documents examined by us are genuine, (ii) all documents submitted to us as originals are authentic and all documents submitted to us as copies conform to the originals of those documents, (iii) the Registration Statement, and any amendments thereto (including post-effective amendments), will have become effective, (iv) a Prospectus Supplement will have been prepared and filed with the Commission describing the Securities offered thereby, (v) all Securities will be issued and sold in compliance with applicable federal and state securities laws and in the manner specified in the Registration Statement and the applicable Prospectus Supplement, (vi) the Indentures relating to the Debt Securities and a warrant agreement (“Warrant Agreement”) relating to the Warrants will each be duly authorized, executed and delivered by the parties thereto, (vii) the Subsidiary Guarantor is duly organized under the laws of the State of Louisiana and is validly existing and in good standing under the laws of that jurisdiction, (viii) each person signing the Indentures and a Warrant Agreement will have the legal capacity and authority to do so, (ix) at the time of any offering or sale of any shares of Common Stock and/or Preferred Stock, that the Company shall have such number of shares of Common Stock and/or Preferred Stock, as set forth in such offering or sale, authorized or created and available for issuance, (x) 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 (xi) any Securities issuable upon conversion, exchange or exercise of any Debt Securities, Preferred Stock, Depositary Shares or Warrants being offered will have been duly authorized, created and, if appropriate, reserved for issuance upon such conversion, exchange or exercise.

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

1. When (a) the applicable Indenture relating either to senior Debt Securities or subordinated Debt Securities and, if applicable, the related Guarantee have been duly qualified under the Trust Indenture Act of 1939, as amended, (b) the board of directors of the Company (or a committee thereof) and, if applicable, the sole member of the Subsidiary Guarantor have taken all necessary corporate action to approve the issuance and terms of any such Debt Securities and, if applicable, the related Guarantee, (c) the terms of such Debt Securities and, if applicable, the related Guarantee and of their issuance and sale have been duly established in conformity with the applicable Indenture 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 or the Subsidiary Guarantor and so as to comply with any requirements or restrictions imposed by any court or governmental body having jurisdiction over the Company or the Subsidiary Guarantor, (d) any shares of Common Stock issuable upon the conversion of such Debt Securities, if applicable, have been duly and validly authorized for issuance and (e) such Debt Securities (which may include the related Guarantee) have been duly executed and authenticated in accordance with the applicable Indenture and issued and sold as contemplated in the Registration Statement and upon payment of the consideration for such Debt Securities as provided for in the applicable definitive purchase, underwriting or similar agreement, such Debt Securities and, if applicable, the related Guarantee will be legally issued and will constitute valid and legally binding obligations of the Company and the Subsidiary Guarantor, respectively, enforceable against the Company and the Subsidiary Guarantor, respectively, in accordance with their terms, except as such enforcement is subject to any applicable bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium and similar laws relating to or affecting creditors’ rights generally and to general equitable principles (regardless of whether enforcement is sought in a proceeding in equity or at law);

2. With respect to shares of Common Stock, when (a) the board of directors of the Company has taken all necessary corporate action to approve the issuance and terms of the offering thereof and related matters; and (b) certificates representing the shares of Common Stock have been duly executed, countersigned, registered and delivered either (i) in accordance with the

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applicable definitive purchase, underwriting or similar agreement approved by the board of directors of the Company, then upon payment of the consideration therefor (not less than the par value of the Common Stock) provided for therein; or (ii) 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 of directors of the Company, for the consideration approved by the board of directors of the Company (not less than the par value of the Common Stock), such shares of Common Stock will be legally issued, fully paid and non-assessable;

3. With respect to shares of any series of Preferred Stock, when (a) the board of directors of the Company 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 (the “Certificate of Designation”); and (b) certificates representing the shares of the series of Preferred Stock have been duly executed, countersigned, registered and delivered either (i) in accordance with the applicable definitive purchase, underwriting or similar agreement approved by the board of directors of the Company, then upon payment of the consideration therefor (not less than the par value of the Preferred Stock) provided for therein; or (ii) 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 of directors of the Company, for the consideration approved by the board of directors of the Company (not less than the par value of the Preferred Stock), the shares of the series of Preferred Stock will be legally issued, fully paid and non-assessable;

4. With respect to the Depositary Shares, when (a) the Company has taken all necessary corporate action to approve the issuance and terms of the Depositary Shares, the terms of the offering thereof and related matters, including the adoption of a Certificate of Designation relating to the Preferred Stock underlying the Depositary Shares and the filing of the Certificate of Designation with the Secretary of State of the State of Delaware; (b) the depositary agreement or agreements relating to the Depositary Shares and the

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related depositary receipts have been duly authorized and validly executed and delivered by the Company and the depositary appointed by the Company; (c) the shares of Preferred Stock underlying the Depositary Shares have been deposited with the depositary under the applicable depositary agreement; and (d) the depositary receipts representing the Depositary Shares have been duly executed, countersigned, registered and delivered in accordance with the appropriate depositary agreement approved by the Company, upon payment of the consideration thereof or provided for in the applicable definitive purchase, underwriting or similar agreement, the Depositary Shares will be legally issued; and

5. With respect to the Warrants, when (a) the board of directors of the Company 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, (b) the 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 (c) the Warrants or certificates representing the Warrants have been duly executed, countersigned, registered, and delivered in accordance with the appropriate agreements relating to the Warrants and the applicable definitive purchase, underwriting, or similar agreement approved by the board of directors of the Company or such officers upon payment of the consideration therefor provided for therein, the Warrants will be legally issued and such Warrants will constitute valid and legally binding obligations of the Company, enforceable against the Company in accordance with their terms, except as such enforcement is subject to any applicable bankruptcy, insolvency (including, without limitation, all laws relating to fraudulent transfers), reorganization, moratorium and similar laws relating to or affecting creditors’ rights generally and to general equitable principles (regardless of whether enforcement is sought in a proceeding in equity or at law).

We express no opinions concerning (i) the validity or enforceability of any provisions contained in the Indentures 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 (ii) 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.

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The foregoing opinions are limited to the laws of the State of New York, the General Corporation Law of the State of Delaware (including the applicable provisions of the Delaware Constitution and the reported judicial decisions interpreting these laws) and the federal laws of the United States of America and we are expressing no opinion as to the effect of the laws of any other jurisdiction, domestic or foreign. In rendering the foregoing opinions, we have relied on the opinion of Cook, Yancey, King & Galloway, APLC for matters involving Louisiana law with respect to the Subsidiary Guarantor, a copy of which is filed as Exhibit 5.2 to the Registration Statement.

We hereby consent to the filing of this opinion as an exhibit to the Registration Statement and to the use of our name in the 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/ Vinson & Elkins L.L.P.

Vinson & Elkins L.L.P.