September 19, 2019

Jielun Zhu
Chief Financial Officer
Suite 802, West Tower, OmniVision
88 Shangke Road, Pudong District
Shanghai, 201210
People's Republic of China

       Re: I-Mab
           Amendment No. 1 to Draft Registration Statement on Form F-1
           Submitted September 5, 2019
           CIK No. 0001778016

Dear Mr. Zhu:

      We have reviewed your amended draft registration statement and have the
comments. 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 providing the requested information and
either submitting
an amended draft registration statement or publicly filing your registration
statement on
EDGAR. If you do not believe our comments apply to your facts and circumstances
or do not
believe an amendment is appropriate, please tell us why in your response.

      After reviewing the information you provide in response to these comments
and your
amended draft registration statement or filed registration statement, we may
have additional

Amendment No. 1 to Draft Registration Statement on Form S-1 submitted September
5, 2019

Prospectus Summary
Overview, page 1

1.     We note your response to prior comment 1 and your continued references
to potentially
       "first-in-class" or "best-in-class" product candidates. We continue to
object to these terms
       as implying your product candidates are likely to be approved and/or
that you will be
       successful in achieving a given market share, which are inappropriate
for you to imply
       given the uncertainty in the development of biologics. As illustrative
examples, we will
       not object to disclosure stating that TJ107 is the first long-acting
recombinant human
 Jielun Zhu
FirstName LastNameJielun Zhu
Comapany 19, 2019
September NameI-Mab
Page 2
September 19, 2019 Page 2
FirstName LastName
         interleukin-7, Enoblituzumab is the most advanced clinical stage
humanized antibody
         targeting T cell checkpoint regulator B7-H3, and TJX7 is the first
humanized neutralizing
         antibody targeting CXCL13 chemokine.
Our Global Strategic Collaborations, page 5

2.       We note your response to comment 15. Please expand your Summary
disclosure to
         disclose that you are the sublicensee under your agreement with
Ferring International
         Center SA related to TJ301, as discussed on page 186.

Collaboration Agreement with MacroGenics (enoblituzumab), page 186

3.       We note your response to prior comment 16 and your revised disclosure
indicating that
         unless prohibited by applicable laws and regulations, you will co-own
all clinical data and,
         to the extent joint ownership is not legally permitted, MacroGenics
will be the sole and
         exclusive owners of such clinical data. Please revise to explain your
reference to
         applicable law or regulation that would preclude you from joint
ownership and, to the
         extent known and applicable, disclose whether you currently qualify
for joint ownership.
PRC Taxation, page 274

4.       We note your response to comment 19, which we reissue in part. Please
revise your
         disclosure to clearly state that the disclosure in this section is the
opinion of named

5.       It appears your are attempting to redact information pursuant to Item
601(b)(10)(iv) of
         Regulation S-K from Exhibits 10.14, 10.15, 10.16, 10.18, 10.19, 10.20,
and 10.21. Please
         revise your Exhibit Index as appropriate and refile these exhibits to
include on the first
         page of each redacted exhibit the legend required by Item
601(b)(10)(iv) of Regulation S-
         K or refile the complete agreement. We note your reference to Rule 406
with respect to
         Exhibits 10.13 and 10.17. Please tell us whether you plan to submit an
application for
         confidential treatment pursuant to Rule 406 or advise.
 Jielun Zhu
September 19, 2019
Page 3

       You may contact Christine Torney at 202-551-3652 or Kevin Vaughn at
202-551-3494 if
you have questions regarding comments on the financial statements and related
matters. Please
contact Jeffrey Gabor at 202-551-2544 or Christine Westbrook at 202-551-5019
with any other

FirstName LastNameJielun Zhu
                                                         Division of
Corporation Finance
Comapany NameI-Mab
                                                         Office of Healthcare &
September 19, 2019 Page 3
cc:       Z. Julie Gao, Esq.
FirstName LastName