United States securities and exchange commission logo January 24, 2022 William Koschak Chief Financial Officer Calyxt, Inc. 2800 Mount Ridge Road Roseville, Minnesota 55113 Re: Calyxt, Inc. Form 10-K for the Year Ended December 31, 2020 Form 10-Q for the Period Ended September 30, 2021 File No. 001-38161 Dear Mr. Koschak: We have completed our review of your filings. 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. Sincerely, Division of Corporation Finance Office of Life Sciences cc: Debra Frimerman