United States securities and exchange commission logo May 27, 2020 W. Wilson Troutman Principal Financial and Accounting Officer Eton Pharmaceuticals, Inc. 21925 W. Field Parkway, Suite 235 Deer Park, IL 60010-7208 Re: Eton Pharmaceuticals, Inc. Form 10-K for the Fiscal Year Ended December 31, 2019 Filed March 5, 2020 File No. 001-38738 Dear Mr. Troutman: We have completed our review of your filing. 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