United States securities and exchange commission logo June 15, 2021 G. Douglas Lanois Chief Financial Officer and Treasurer RMR Mortgage Trust Two Newton Place, 255 Washington Street, Suite 300 Newton, Massachusetts 02458 Re: RMR Mortgage Trust Registration Statement on Form S-4 Filed June 9, 2021 File No. 333-256951 Dear Mr. Lanois: This is to advise you that we have not reviewed and will not review your registration statement. Please refer to Rules 460 and 461 regarding requests for acceleration. We remind you that the company and its management are responsible for the accuracy and adequacy of their disclosures, notwithstanding any review, comments, action or absence of action by the staff. Please contact Hannah Menchel at 202-551-5702 or Erin E. Martin at 202-551-3391 with any questions. Sincerely, Division of Corporation Finance Office of Real Estate & Construction