United States securities and exchange commission logo

                 March 22, 2022

       John Celebi
       President and Chief Executive Officer
       Sensei Biotherapeutics, Inc.
       451 D Street, Suite 710
       Boston, Massachusetts 02210

                                                        Re: Sensei
Biotherapeutics, Inc.
Statement on Form S-3
                                                            Filed March 15,
                                                            File No. 333-263567

       Dear Mr. Celebi:

              This is to advise you that we have not reviewed and will not
review your registration

               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 Michael Davis at 202-551-4385 or Celeste Murphy at
202-551-3257 with
       any questions.


                 Division of Corporation Finance

                 Office of Life Sciences
       cc:                                              Mark Ballantyne