Exhibit 5.1

				Hogan Lovells US LLP Columbia Square 555 Thirteenth Street, NW Washington, DC 20004 T +1 202 637 5600 F +1 202 637 5910 www.hoganlovells.com

June 1, 2015

Board of Trustees

Washington Real Estate Investment Trust

1775 Eye Street, NW

Suite 100

Washington, DC 20006

Ladies and Gentlemen:

We are acting as counsel to Washington Real Estate Investment Trust, a Maryland real estate investment trust (the “Company”), in connection with its registration statement on Form S-3 (the “Registration Statement”), filed with the Securities and Exchange Commission under the Securities Act of 1933, as amended (the “Act”) relating to the proposed public offering of up to 1,000,000 shares of the common shares of beneficial interest, par value $0.01 per share, of the Company (the “Common Shares”), all of which may be sold from time to time on a delayed or continuous basis in connection with the Company’s Direct Dividend Reinvestment and Share Purchase Plan (the “Plan”), as set forth in the prospectus that forms a part of the Registration Statement. 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 telecopies). We also have assumed that (i) the Common Shares will not be issued in violation of the ownership limit contained in the Company’s Articles of Amendment and Restatement, as amended, and (ii) at the time of the offer, issuance and sale of any Shares, no stop order suspending effectiveness of the Registration Statement will have been issued and remain in effect. 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 applicable provisions of Title 8 of the Corporations and Associations Article of the Annotated Code of Maryland, as amended, and applicable provisions of the Maryland General Corporation Law, as amended, currently in effect. We express no opinion herein as to any other laws, statutes, ordinances, rules, or regulations.

Based upon, subject to and limited by the foregoing, we are of the opinion that following (i) effectiveness of the Registration Statement, (ii) issuance and delivery of the Common Shares in the manner and pursuant to the terms described in the Registration Statement and the Plan, and (iii) upon receipt by the Company of the consideration for the Common Shares specified in the Plan, the Common Shares will be validly issued, fully paid, and nonassessable.

This opinion letter has been prepared for use in connection with the Registration Statement. We assume no obligation to advise you of any changes in the foregoing subsequent to the effective date of the Registration Statement.

We hereby consent to the filing of this opinion letter as Exhibit 5.1 to the Registration Statement and to the reference to this firm under the caption “Legal Matters” in the prospectus constituting a part of the Registration Statement. In giving this consent, we do not thereby admit that we are an “expert” within the meaning of the Securities Act of 1933, as amended.