Exhibit 5.1

Partners:
Brett Basdeo	***
John Cartwright	*
Audrey Coker	*
John Crook	*
Mark Cummings	*****
Natalie Curtis	****
James Gaden	****
Thomas Granger	**
Kristen Kwok	**
Wing Lam	*
William Lee	*
Thomas Pugh	*****
Andrew Randall	**
Victoria Raymond	*
Rupen Shah	*****
Colette Wilkins KC	***
Denise Wong	**

29 March 2024  Our Ref: MRC/KH/A6545-H26452

Adagene Inc.
c/o Walkers Corporate Limited

190 Elgin Avenue, George Town

Grand Cayman KY1-9008

Cayman Islands

Dear Sir or Madam

ADAGENE INC.

We have acted as Cayman Islands legal advisers to Adagene Inc. (the "Company") in connection with the registration for issuance and sale, from time to time, by the Company, through Leerink Partners LLC, of up to US$100,000,000 of American depositary shares (the “ADSs”), each representing 1.25 ordinary shares of a par value of US$0.0001 per ordinary share of the Company (“Shares”) as contemplated by (i) the Registration Statement (as defined below), (ii) the Base Prospectus (as defined below) and (iii) the Prospectus Supplement (as defined below) relating to the sale of such Ordinary Shares in the form of ADSs, from time to time, with an aggregate offering price of up to US$100 million pursuant to the Sales Agreement (as defined below) (the “Placement Shares”). We are furnishing this opinion as exhibit 5.1, 8.1 and 23.2 to the Registration Statement.

For the purposes of giving this opinion, we have examined and relied upon the originals, copies or translations of the documents listed in Schedule 1.

In giving this opinion we have relied upon the assumptions set out in Schedule 2, which we have not independently verified.

We are Cayman Islands Attorneys at Law and express no opinion as to any laws other than the laws of the Cayman Islands in force and as interpreted at the date of this opinion. We have not, for the purposes of this opinion, made any investigation of the laws, rules or regulations of any other jurisdiction. Except as explicitly stated herein, we express no opinion in relation to any representation or warranty contained in any of the documents cited in this opinion nor upon matters of fact or the commercial terms of the transactions the subject of this opinion.

Based upon the examinations and assumptions stated herein and upon such searches as we have conducted and having regard to legal considerations which we consider relevant, and subject to the qualifications set out in Schedule 3, and under the laws of the Cayman Islands, we give the following opinions in relation to the matters set out below.

Walkers (Hong Kong)

滙嘉律師事務所 (香港)

15th Floor, Alexandra House, 18 Chater Road, Central, Hong Kong

T +852 2284 4566 F +852 2284 4560

Bermuda | British Virgin Islands | Cayman Islands | Dubai | Guernsey | Hong Kong | Ireland | Jersey | London | Singapore

^*England and Wales; ^**BVI; ^***Cayman Islands; ^****New South Wales (Australia); ^*****Bermuda

WALKERS Page 2

1. The Company is an exempted company duly incorporated with limited liability, validly existing under the laws of the Cayman Islands and is in good standing with the Registrar of Companies in the Cayman Islands (the "Registrar").

2. The authorised share capital of the Company is currently US$80,000 divided into 800,000,000 shares comprising (i) 640,000,000 ordinary shares of a par value of US$0.0001 each, and (ii) 160,000,000 shares of a par value of US$0.0001 each of such class or classes (however designated) as the Company’s board of directors may determine in accordance with the Memorandum and Articles (as defined in Schedule 1).

3. With respect to the Placement Shares when (a) the provisions of the Sales Agreement approved by the Company’s board of directors have been satisfied and payment of the consideration specified therein (being not less than their par value) has been made; and (b) in the case of Ordinary Shares only, valid book-entry notations are made in the register of members of the Company, then the Placement Shares, will have been duly authorised and validly issued, fully paid and non-assessable (meaning that no additional sums may be levied on the holder thereof by the Company).

4. The statements under the caption “Taxation” in the Prospectus forming part of the Registration Statement, to the extent that they constitute statements of Cayman Islands law, are accurate in all material respects.

We hereby consent to the use of this opinion in, and the filing hereof, as an exhibit to the Registration Statement and further consent to all references to our name in the Registration Statement. In giving such consent, we do not thereby admit that we come within the category of persons whose consent is required under Section 7 of the U.S. Securities Act of 1933, as amended, or the rules and regulations of the Commission promulgated thereunder.

This opinion is limited to the matters referred to herein and shall not be construed as extending to any other matter or document not referred to herein. This opinion is given solely for your benefit and the benefit of your legal advisers acting in that capacity in relation to this transaction and may not be relied upon by any other person without our prior written consent.

This opinion shall be construed in accordance with the laws of the Cayman Islands.

Yours faithfully

/s/ Walkers (hong kong)

Walkers (hong kong)

WALKERS Page 3

Schedule 1

LIST OF DOCUMENTS EXAMINED

1. The Certificate of Incorporation dated 25 February 2011, the Seventh Amended and Restated Memorandum and Articles of Association as adopted by special resolutions passed on 19 January 2021 (the "Memorandum and Articles"), the Register of Members printed on 28 March 2024 (the "Register of Members"), Register of Directors and Officers of the Company provided to us on 21 January 2024, copies of which have been provided to us by the Company (together the "Company Records").

2. The Cayman Online Registry Information System (CORIS), the Cayman Islands’ General Registry's online database, searched on 28 March 2024.

3. The Register of Writs and other Originating Process of the Grand Court kept at the Clerk of Court's Office, George Town, Grand Cayman (the "Court Register"), as at 9.00 a.m. Cayman Islands time on 27 March 2024 (the "Search Time").

4. A Certificate of Good Standing dated 26 March 2024 in respect of the Company issued by the Registrar (the "Certificate of Good Standing").

5. A copy of executed written resolutions of the Board of Directors of the Company dated 29 February 2024 setting out the resolutions relating to the Prospectus and Sales Agreement (the "Resolutions").

6. The Company's registration statement on Form F-3 (Registration No. 333-264486) initially filed by the Company with the United States Securities and Exchange Commission on 26 April 2022 (the "Registration Statement").

7. The base prospectus contained in the Registration Statement (the "Base Prospectus").

8. The prospectus supplement dated 29 March 2024 relating to the offer and sale of the Ordinary Shares in the form of ADSs pursuant to the Sales Agreement (the "Prospectus Supplement").

9. A copy of the sales agreement dated 29 March 2024 between the Company and Leerink Partners LLC (the "Sales Agreement").

WALKERS Page 4

Schedule 2

ASSUMPTIONS

1. All authorisations, approvals, consents, licences and exemptions required by, and all filings and other steps required of each of the parties to the Registration Statement outside the Cayman Islands to ensure the legality, validity and enforceability of the Registration Statement have been or will be duly obtained, made or fulfilled and are and will remain in full force and effect and any conditions to which they are subject have been satisfied.

2. The Resolutions are and shall remain in full force and effect and have not been and will not be rescinded or amended.

3. The originals of all documents examined in connection with this opinion are authentic.  The documents conform in every material respect to the latest draft of the same produced to us and, where provided in successive drafts, have been marked up to indicate all changes to such documents.

4. The Registration Statement and the documents or agreements referred to therein have been or will be duly authorised, executed and delivered by or on behalf of all relevant parties prior to the issue and sale of the Securities and will be legal, valid, binding and enforceable against all relevant parties in accordance with their terms.

5. On the date of issue of the Ordinary Shares, the Company shall have sufficient authorised but unissued share capital available.

6. The Resolutions have been duly executed (and where by a corporate entity such execution has been duly authorised if so required) by or on behalf of each Director and the signatures and initials thereon are those of a person or persons in whose name the Resolutions have been expressed to be signed.

7. The Company will on issue of the relevant Ordinary Shares receive, consideration in money or money’s worth for each share when issued, such consideration in any event not being less than the stated par or nominal value of each share.

8. The Company will on issue of the relevant Ordinary Shares have, issued and sold the shares in the manner contemplated by the Registration Statement and the documents or agreements referred to therein and otherwise in compliance with all applicable laws.

9. There is nothing under any law (other than the laws of the Cayman Islands) which would or might affect any of the opinions set forth herein.

10. Any power of attorney given to execute any document or Resolutions was duly executed, the named attorneys were duly appointed with full power granted to each of them and the power of attorney remains in full force and effect and have not been revoked or varied.

WALKERS Page 5

Schedule 3

QUALIFICATION

1. The term "enforceable" and its cognates as used in this opinion means that the obligations assumed by any party under the documents are of a type which the Courts enforce.  This does not mean that those obligations will necessarily be enforced in all circumstances in accordance with their terms.  In particular:

(a) enforcement of obligations and the priority of obligations may be limited by bankruptcy, insolvency, liquidation, restructuring, reorganisation, readjustment of debts or moratorium and other laws of general application relating to or affecting the rights of creditors or by prescription or lapse of time;

(b) enforcement may be limited by general principles of equity and, in particular, the availability of certain equitable remedies such as injunction or specific performance of an obligation may be limited where a Court considers damages to be an adequate remedy;

(c) claims may become barred under statutes of limitation or may be or become subject to defences of set-off, counterclaim, estoppel and similar defences;

(d) where obligations are to be performed in a jurisdiction outside the Cayman Islands, they may not be enforceable in the Cayman Islands to the extent that performance would be illegal under the laws of, or contrary to the public policy of, that jurisdiction;

(e) a judgment of a Court may be required to be made in Cayman Islands dollars;

(f) to the extent that any provision of the documents is adjudicated to be penal in nature, it will not be enforceable in the Courts; in particular, the enforceability of any provision of the documents that is adjudicated to constitute a secondary obligation which imposes a detriment on the contract-breaker out of all proportion to any legitimate interest of the innocent party in the enforcement of the primary obligation may be limited;

(g) to the extent that the performance of any obligation arising under the documents would be fraudulent or contrary to public policy, it will not be enforceable in the Courts;

(h) in the case of an insolvent liquidation of any of the companies, its liabilities are required to be translated into the functional currency of such Company (being the currency of the primary economic environment in which it operated as at the commencement of the liquidation) at the exchange rates prevailing on the date of commencement of the voluntary liquidation or the day on which the winding up order is made (as the case may be);

WALKERS Page 6

(i) a Court will not necessarily award costs in litigation in accordance with contractual provisions in this regard; and

(j) the effectiveness of terms in the documents excusing any party from a liability or duty otherwise owed or indemnifying that party from the consequences of incurring such liability or breaching such duty shall be construed in accordance with, and shall be limited by, applicable law, including generally applicable rules and principles of common law and equity.

2. Our opinion as to good standing is based solely upon receipt of the Certificate of Good Standing issued by the Registrar. The Company shall be deemed to be in good standing under section 200A of the Companies Act (as amended) of the Cayman Islands on the date of issue of the certificate if all fees and penalties under the Companies Act have been paid and the Registrar has no knowledge that the Company is in default under the Companies Act.

3. We express no opinion upon any provisions in the Memorandum and Articles or any document which contains a reference to any law or statute that is not a Cayman Islands law or statute.