Exhibit 5.1

		ONE SHELL PLAZA 910 LOUISIANA HOUSTON, TEXAS 77002-4995   TEL +1 713.229.1234 FAX +1 713.229.1522 www.bakerbotts.com		AUSTIN BEIJING BRUSSELS DALLAS DUBAI HONG KONG HOUSTON		LONDON MOSCOW NEW YORK PALO ALTO RIYADH SAN FRANCISCO WASHINGTON

February 6, 2018

Oceaneering International, Inc.

11911 FM 529

Houston, Texas 77041

Ladies and Gentlemen:

Oceaneering International, Inc., a Delaware corporation (“Oceaneering”), has engaged us to render the opinions expressed below in connection with Oceaneering’s offering of $300,000,000 aggregate principal amount of senior notes due February 1, 2028 (the “Notes”), which Oceaneering is offering under the registration statement on Form S-3 (Reg. No. 333-222774) filed by Oceaneering with the Securities and Exchange Commission (the “SEC”) under the Securities Act of 1933, as amended (the “Securities Act”), which relates to Oceaneering’s offering and sale of senior debt securities under Rule 415 under the Securities Act. In this letter, “Registration Statement” means that registration statement, when it became effective under the Securities Act.

Oceaneering will issue the Notes under the Senior Indenture dated as of November 21, 2014 between it and Wells Fargo Bank, National Association, as trustee (the “Trustee”), relating to senior debt securities of Oceaneering (the “Base Indenture”), as supplemented by the Second Supplemental Indenture to be dated as of February 6, 2018 between Oceaneering and the Trustee (the “Supplemental Indenture” and, together with the Base Indenture, the “Indenture”).

For purposes of the opinions we express below, we have examined, among other documents, originals or copies, certified or otherwise identified, of the following:

In giving the opinions set forth herein, we have relied, to the extent we deemed appropriate, with respect to factual matters, on certificates, statements or other representations of officers or other representatives of Oceaneering and of public officials, and we have assumed, without independent investigation, that all signatures on documents we have examined are genuine, all documents submitted to us as originals are authentic, all documents submitted to us as certified or other copies conform to the original copies of those documents and those original copies are authentic.

On the basis of and subject to the assumptions, limitations and qualifications set forth herein, we are of the opinion that the Notes will, when they have been duly executed, authenticated, issued and delivered in accordance with the provisions of the Indenture, and duly purchased and paid for in accordance with the provisions of the Underwriting Agreement, constitute legal, valid and binding obligations of Oceaneering, enforceable against Oceaneering in accordance with their terms, except as that enforcement is subject to the effects of (a) any applicable bankruptcy, insolvency, reorganization, moratorium, fraudulent conveyance or transfer or other laws relating to or affecting creditors’ rights generally, (b) general principles of equity (regardless of whether such enforceability is considered in a proceeding in equity or at law) and comity and (c) public policy, applicable law relating to fiduciary duties and indemnification and any implied covenants of good faith and fair dealing.

We limit the opinions we express above in all respects to matters of the laws of the State of New York, as in effect on the date hereof.

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We hereby consent to the filing of this opinion of counsel as Exhibit 5.1 to Oceaneering’s current report on Form 8-K reporting the offering of the Notes. We also consent to the reference to our firm under the heading “Legal Matters” in the Prospectus. In giving this consent, we do not hereby admit we are in the category of persons whose written consent Section 7 of the Securities Act requires to be filed.

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