EX-5.1

Exhibit 5.1

Hogan Lovells US LLP

1735 Market Street, Floor 23

Philadelphia, PA 19103

T +1 267 675 4600

F +1 267 675 4601

www.hoganlovells.com

February 12, 2021

Board of Directors

EyePoint Pharmaceuticals, Inc.

480 Pleasant Street

Watertown, MA 02472

Ladies and Gentlemen:

We are acting as counsel to EyePoint Pharmaceuticals, Inc., a Delaware corporation (the “Company”), in connection with its registration statement on Form S-3 (as may be amended from time to time, the “Registration Statement”), filed with the Securities and Exchange Commission relating to the proposed resale by the selling stockholder listed in the Registration Statement of up to 3,010,722 shares (the “Shares”) of common stock, $0.001 par value per share, of the Company (the “Common Stock”), that were issued to the selling stockholder pursuant to that certain Share Purchase Agreement, dated as of December 31, 2020 (as amended, the “Agreement”), in a private placement that closed on December 31, 2020, all of which may be sold from time to time and on a delayed or continuous basis, as set forth in the prospectus which forms a part of the Registration Statement (the “Prospectus”). This opinion letter is furnished to you at your request to enable you to fulfill the requirements of Item 601(b)(5) of Regulation S-K, 17 C.F.R. § 229.601(b)(5), in connection with the Registration Statement.

For purposes of this opinion letter, we have examined copies of such agreements, instruments and documents as we have deemed an appropriate basis on which to render the opinions hereinafter expressed. In our examination of the aforesaid documents, we have assumed the genuineness of all signatures, the legal capacity of all natural persons, the accuracy and completeness of all documents submitted to us, the authenticity of all original documents, and the conformity to authentic original documents of all documents submitted to us as copies (including pdfs). As to all matters of fact, we have relied on the representations and statements of fact made in the documents so reviewed, and we have not independently established the facts so relied on. This opinion letter is given, and all statements herein are made, in the context of the foregoing.

This opinion letter is based as to matters of law solely on the Delaware General Corporation Law, as amended. We express no opinion herein as to any other statutes, rules or regulations. As used herein, the term “Delaware General Corporation Law, as amended” includes the statutory provisions contained therein, all applicable provisions of the Delaware Constitution and reported judicial decisions interpreting these laws.

Hogan Lovells US LLP is a limited liability partnership registered in the District of Columbia. “Hogan Lovells” is an international legal practice that includes Hogan Lovells US LLP and Hogan Lovells International LLP, with offices in: Alicante Amsterdam Baltimore Beijing Birmingham Boston Brussels Colorado Springs Denver Dubai Dusseldorf Frankfurt Hamburg Hanoi Ho Chi Minh City Hong Kong Houston Johannesburg London Los Angeles Luxembourg Madrid Mexico City Miami Milan Minneapolis Monterrey Moscow Munich New York NorthernVirginia Paris Perth Philadelphia Rome San Francisco São Paulo Shanghai Silicon Valley Singapore Sydney Tokyo Warsaw Washington DC Associated offices: Budapest Jakarta Riyadh Shanghai FTZ Ulaanbaatar Zagreb. Business Service Centers: Johannesburg Louisville. Legal Services Center: Berlin. For more information see www.hoganlovells.com