UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-A

FOR REGISTRATION OF CERTAIN CLASSES OF SECURITIES

PURSUANT TO SECTION 12(b) OR 12(g) OF THE

SECURITIES EXCHANGE ACT OF 1934

1001 Fannin Street, Suite 1500

Houston, Texas 77002

(Address of principal executive offices and zip code)

Securities to be registered pursuant to Section 12(b) of the Act:

If this form relates to the registration of a class of securities pursuant to Section 12(b) of the Exchange Act and is effective pursuant to General Instruction A.(c) or (e), check the following box.  ☒

If this form relates to the registration of a class of securities pursuant to Section 12(g) of the Exchange Act and is effective pursuant to General Instruction A.(d) or (e), check the following box.  ☐

If this form relates to the registration of a class of securities concurrently with a Regulation A offering, check the following box.  ☐

Securities Act registration statement file number to which this form relates:

333-217976.

Securities to be registered pursuant to Section 12(g) of the Act:

None.

INFORMATION REQUIRED IN REGISTRATION STATEMENT

A description of the common units representing limited partner interests in Oasis Midstream Partners LP (the “Registrant”) is set forth under the captions “Summary—The Offering,” “Our Cash Distribution Policy and Restrictions on Distributions,” “How We Make Distributions To Our Partners,” “Description of the Common Units,” “The Partnership Agreement,” “Units Eligible for Future Sale” and “Material U.S. Federal Income Tax Consequences” in the prospectus included in the Registrant’s Registration Statement on Form S-1 (Registration No. 333-217976), initially filed with the Securities and Exchange Commission on May 12, 2017 under the Securities Act of 1933, as amended, and will be set forth in any prospectus filed in accordance with Rule 424(b) thereunder, which description is incorporated herein by reference.

Pursuant to the Instructions as to Exhibits with respect to Form 8-A, no exhibits are required to be filed because no other securities of the Registrant are registered on the New York Stock Exchange and the securities registered hereby are not being registered pursuant to Section 12(g) of the Exchange Act.

SIGNATURE

Pursuant to the requirements of Section 12 of the Securities Exchange Act of 1934, the registrant has duly caused this registration statement to be signed on its behalf by the undersigned, thereto duly authorized.

Date: September 20, 2017