United States securities and exchange commission logo

                            December 29, 2022

       Oliver Schacht
       Chief Executive Officer
       OpGen, Inc.
       9717 Key West Avenue, Suite 100
       Rockville, MD 20850

                                                        Re: OpGen, Inc.
Statement on Form S-1
                                                            Response dated
December 21, 2022
                                                            File No. 333-268648

       Dear Oliver Schacht:

               We have reviewed your amended registration statement and have
the following
       comment. In some of our comments, we may ask you to provide us with
information so we may
       better understand your disclosure.

              Please respond to this letter by amending your registration
statement and providing the
       requested information. If you do not believe our comment applies to your
facts and
       circumstances or do not believe an amendment is appropriate, please tell
us why in your

               After reviewing any amendment to your registration statement and
the information you
       provide in response to the comment, we may have additional comments.
Unless we note
       otherwise, our references to the prior comment is to the comment in our
December 21, 2022

       Registration Statement on Form S-1 filed December 21, 2022


   1.                                                   We acknowledge your
response to our prior comment, including your proposed revised
                                                        disclosure. Please
expand your proposed revised disclosure regarding the disparate rights
                                                        to also explain other
types of material provisions covered by the purchase agreement, such
                                                        as your representations
and other types of covenants. In addition, please add other
                                                        appropriate disclosures
in the prospectus explaining this potential difference in rights,
                                                        including a risk
 Oliver Schacht
OpGen, Inc.LastNameOliver Schacht
December   NameOpGen,
              2022      Inc.
Page 2    29, 2022 Page 2
FirstName LastName
       Please contact Sean Healy at 202-551-5586 or Dorrie Yale at 202-551-8776
with any


                                                         Division of
Corporation Finance
                                                         Office of Industrial
Applications and
cc:      Peter Jaslow, Esq.