United States securities and exchange commission logo November 20, 2023 Oliver Schacht, Ph.D. Chief Executive Officer and Director OpGen, Inc. 9717 Key West Avenue, Suite 100 Rockville, MD 20850 Re: OpGen, Inc. Registration Statement on Form S-3 Filed November 13, 2023 File No. 333-275516 Dear Oliver Schacht: 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 Juan Grana at 202-551-6034 with any questions. Sincerely, Division of Corporation Finance Office of Industrial Applications and Services cc: Peter Jaslow, Esq.