Exhibit 8.1

Fried, Frank, Harris, Shriver & Jacobson LLP   801 17^th Street, NW Washington, DC 20006 Tel:+1.202.639.7000 Fax:+1.202.639.7003 www.friedfrank.com

September 23, 2021

Navios Maritime Partners L.P.

7 Avenue de Grande Bretagne, Office 11B2

Monte Carlo, MC 98000 Monaco

Ladies and Gentlemen:

We have acted as counsel to Navios Maritime Partners L.P., a Republic of the Marshall Islands limited partnership (“Parent”), in connection with the Merger, as defined in the Agreement and Plan of Merger (the “Merger Agreement”), dated as of August 25, 2021, by and among Parent, Navios Acquisition Merger Sub., Inc., a Republic of the Marshall Islands corporation and a wholly owned subsidiary of Parent (“Merger Sub”) and Navios Maritime Acquisition Corp., a Republic of the Marshall Islands corporation (“NNA”). All capitalized terms used but not otherwise defined herein have the meaning ascribed to them in the Registration Statement.

At your request, and in connection with the filing of the Form F-4 by Parent with the Securities and Exchange Commission (File No. 333-259526) (the “Registration Statement”), including the joint proxy statement/prospectus forming a part thereof, we are rendering our opinion regarding certain U.S. federal income tax matters.

In connection with this opinion, and with your consent, we have reviewed and relied upon the accuracy and completeness, without independent investigation or verification, of the following: (i) the Merger Agreement; (ii) the Registration Statement, including the joint proxy statement/prospectus forming a part thereof; (iii) the factual statements and representations made by and on behalf of NNA, Parent and Merger Sub, in their respective tax representation letters (the “Tax Representation Letters”), dated as of the date hereof and delivered to us for purposes of this opinion and pursuant to Section 5.8(a) of the Merger Agreement; and (iv) such other documents, information and materials as we have deemed necessary or appropriate.

In rendering this opinion, we have assumed, with your permission, that: (1) all parties to the Merger Agreement, and to any other documents reviewed by us, have acted and will act in accordance with the terms of the Merger Agreement and such other documents; (2) the Merger will be consummated at the Effective Time pursuant to and in accordance with the terms and conditions set forth in the Merger Agreement, without the waiver or modification of any such terms and conditions, and as described in the Registration Statement; (3) all facts, information, statements, covenants, representations, warranties and agreements made by or on behalf of NNA, Parent and Merger Sub, in the Merger Agreement, the Registration Statement and the Tax Representation Letters (all such facts, information, statements, covenants representations, warranties and agreements made by such persons in such documents are collectively referred to as the “Relevant Statements”) are as of the date hereof and, at all times up to and including the Effective Time (or, if the Optional Second Merger is consummated, at all times up to and including the effective time of the Optional Second Merger (the “Completion Time”)), will continue to be true, complete and correct; (4) all Relevant Statements that are qualified by the knowledge and/or belief of any person or entity are and, at all times up to and including (i) if the Optional Second Merger is not consummated, the Effective Time or (ii) if the Optional Second Merger is consummated, the Completion Time, will continue to be true, complete and correct as though not so qualified; (5) as to all matters as to which any person or entity represents that it is not a party to, does not have, or is not aware of any plan, intention, understanding or agreement, there is in fact no plan, intention, understanding or agreement and, at all times up to and including the Effective Time, or if the Optional Second Merger is consummated, the Completion Time, there will be no plan, intention, understanding or agreement; and (6) for U.S. federal income tax purposes NNA, Parent and Merger Sub will treat the Merger, either alone or together with the Optional Second Merger, as a “reorganization” within the meaning of Section 368(a) of

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Fried, Frank, Harris, Shriver & Jacobson LLP

Navios Maritime Partners L.P..

February 17, 2021

Page 2

the Internal Revenue Code of 1986, as amended (the “Code”), and will not treat Section 367(a) of the Code as causing Parent to be treated as other than a corporation with respect to any transfer of property thereto in connection with the Merger (other than, in certain circumstances, a transfer by a holder of Navios Acquisition Common Shares that is a United States person and that holds 5% or more by vote or by value (within the meaning of Treasury Regulations Section 1.367(a)-3(b)(1)(i)) of Parent immediately following the Merger). We also have assumed the authenticity of original documents, the accuracy of copies, the genuineness of signatures and the legal capacity of signatories. Moreover, we have assumed that all facts, information, statements and representations contained in the documents we have reviewed were true, complete and correct at the time made and will continue to be true, complete and correct in all respects at all times up to and including the Effective Time, or if the Optional Second Merger is consummated, the Completion Time and that all such facts, information, statements and representations can be established to the Internal Revenue Service or courts, if necessary, by clear and convincing evidence. If any of the assumptions described above are untrue for any reason, or if the Merger is consummated other than in accordance with the terms and conditions set forth in the Merger Agreement, our opinion as expressed below may be adversely affected.

Our opinion is based on the Code, the United States Treasury Regulations, case law and published rulings and other pronouncements of the Internal Revenue Service, as in effect on the date hereof. No assurances can be given that such authorities will not be amended or otherwise changed at any time, possibly with retroactive effect. We assume no obligation to advise you of any such subsequent changes, or to update or supplement this opinion to reflect any change in facts, circumstances or law after the date hereof. Any change in the applicable law or regulations, or any new administrative or judicial interpretation of the applicable law or regulations, may affect the continuing validity of our opinion.

Based upon and subject to the foregoing, and to the qualifications and limitations set forth herein, and in reliance upon the representations and assumptions described herein, we hereby confirm that the section of the Registration Statement entitled “Material U.S. Federal Income Tax Consequences of the Merger” sets forth our opinion as to the material U.S. federal income tax consequences of the Merger, either alone or together with the Optional Second Merger, to U.S. Holders of Navios Acquisition Common Shares.

Our opinion relates solely to the specific matters set forth above, and no opinion is expressed, or should be inferred, as to any other U.S. federal, state, local or non-U.S. income, estate, gift, transfer, sales, use or other tax consequences that may result from the Merger. Our opinion is limited to legal rather than factual matters and has no official status or binding effect of any kind. Accordingly, we cannot assure you that the Internal Revenue Service or a court will agree with our opinion.

The opinion expressed herein is being furnished in connection with the filing of the Registration Statement and may not be used or relied upon for any other purpose without our prior written consent. We hereby consent to the filing of this opinion with the Securities and Exchange Commission as Exhibit 8.1 to the Registration Statement. 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 of 1933, as amended, or the rules or regulations of the Securities and Exchange Commission promulgated thereunder.

Very truly yours,

/s/ FRIED, FRANK, HARRIS, SHRIVER & JACOBSON LLP