Exhibit 5.1

	ATTORNEYS AT LAW 777 EAST WISCONSIN AVENUE MILWAUKEE, WI 53202-5306 414.271.2400 TEL 414.297.4900 FAX foley.com
February 9, 2024	CLIENT/MATTER NUMBER 082961-0139

Hennessy Advisors, Inc.

7250 Redwood Blvd., Suite 200

Novato, California 94945

Ladies and Gentlemen:

We have acted as counsel for Hennessy Advisors, Inc., a California corporation (the “Company”), in conjunction with the preparation of a Registration Statement on Form S-8 (the “Registration Statement”) to be filed by the Company with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Securities Act”), relating to 3,835,000 shares (the “Registered Shares”) of the Company’s common stock, no par value per share (the “Common Stock”) that may be issued pursuant to the Hennessy Advisors, Inc. 2024 Omnibus Incentive Plan (the “Plan”).

In connection with our representation, we have examined: (i) the Plan and related documents; (ii) the Registration Statement, including the exhibits (including those incorporated by reference) constituting a part of the Registration Statement; (iii) the Amended and Restated Articles of Incorporation and the Fifth Amended and Restated Bylaws of the Company; (iv) the resolutions of the Company’s Board of Directors relating to the Plan and the issuance of Common Stock thereunder; and (v) such other corporate proceedings, documents and records as we have deemed necessary or appropriate to enable us to render this opinion. In our examination of the above-referenced documents, we have assumed the genuineness of all signatures, the authenticity of all documents, certificates and instruments submitted to us as originals and the conformity with the originals of all documents submitted to us as copies.

It is understood that this opinion is to be used only in connection with the offer and sale of the Registered Shares while the Registration Statement is effective.

This opinion is being furnished in connection with the requirements of Item 601(b)(5) of Regulation S-K under the Securities Act, and no opinion is expressed herein as to any matter pertaining to the contents of the Registration Statement or the prospectus that forms a part thereof, other than as expressly stated herein with respect to the issuance of the Registered Shares.

Based upon the foregoing, we are of the opinion that each of the Registered Shares, if and when issued by the Company pursuant to the terms and conditions of the Plan and as contemplated by the Registration Statement, will be legally issued, fully paid and nonassessable.

BOSTON BRUSSELS CHICAGO DETROIT JACKSONVILLE LOS ANGELES MADISON MIAMI MILWAUKEE NEW YORK ORLANDO SACRAMENTO SAN DIEGO SAN DIEGO/DEL MAR SAN FRANCISCO SHANGHAI SILICON VALLEY TALLAHASSEE TAMPA TOKYO WASHINGTON, D.C.

Hennessy Advisors, Inc.
February 9, 2024
Page 2

We consent to the use of this opinion as an exhibit to the Registration Statement. In giving our consent, we do not admit that we are “experts” within the meaning of Section 11 of the Securities Act or within the category of persons whose consent is required by Section 7 of the Securities Act.

Very truly yours,

/s/ Foley & Lardner LLP

Foley & Lardner LLP