Distribution Report by Development Bank - Form DSTRBRPT

21 May 2024

Asian Development Bank
6 ADB Avenue, Mandaluyong City
1550 Metro Manila
Philippines

Ladies and Gentlemen:

We have acted as special United States counsel to the several Managers (the "Managers") named in the terms agreement dated as of 17 May 2024 between the Asian Development Bank (the "ADB") and the Managers, in connection with the offering by the ADB of U.S.$3,500,000,000 principal amount of 4.875 per cent. Global Notes due 21 May 2026 (Series 1630-00-1) (the "Notes") pursuant to the ADB's Global Medium-Term Note Program (the "Program"). This opinion letter is furnished as an exhibit to a report of the ADB of even date herewith filed with respect to the Notes pursuant to Regulation AD adopted by the Securities and Exchange Commission under Section 11(a) of the Asian Development Bank Act.

In arriving at the opinion expressed below, we have reviewed the following documents:

(a)

the Terms and Conditions of the Notes contained in the prospectus dated 9 December 2020 relating to the Program (as amended and supplemented and including the documents incorporated by reference therein) and the pricing supplement dated 17 May 2024;

(b)

the standard provisions dated as of 9 December 2020 relating to the issuance of Notes by the ADB;

(c)

an executed copy of the uniform fiscal agency agreement dated as of 20 July 2006, the letter of agreement dated 20 July 2006 from the ADB to the Federal Reserve Bank of New York ("FRBNY") and the letter of acknowledgment dated 8 August 2006 from the FRBNY to the ADB;

Asian Development Bank, p. 2

(d)

the letter of instruction dated 17 May 2024 from the ADB to the FRBNY, authorizing and requesting delivery of the Notes; and

In addition, we have reviewed the originals or copies certified or otherwise identified to our satisfaction of all such corporate records of the ADB and such other documents, and we have made such investigations of law, as we have deemed appropriate as a basis for the opinion expressed below.

In rendering the opinion expressed below, we have assumed the authenticity of all documents submitted to us as originals and the conformity to the originals of all documents submitted to us as copies.

Based on the foregoing, and subject to the further assumptions and qualifications set forth below, it is our opinion that the Notes, when they have been duly issued, delivered in book-entry form to or on behalf of the Managers and paid for, will constitute the valid, binding and enforceable obligations of the ADB.

Insofar as the foregoing opinion relates to the validity, binding effect or enforceability of any agreement or obligation of the ADB, (a) we have assumed that the ADB and each other party to such agreement or obligation has satisfied those legal requirements that are applicable to it to the extent necessary to make such agreement or obligation enforceable against it (except that no such assumption is made as to the ADB regarding matters of federal law of the United States of America or the law of the State of New York that in our experience normally would be applicable with respect to such agreement or obligation), (b) such opinion is subject to applicable bankruptcy, insolvency and similar laws affecting creditors' rights generally and to general principles of equity and (c) such opinion is subject to the effect of judicial application of foreign laws or foreign governmental actions affecting creditors' rights.

The foregoing opinion is limited to the federal law of the United States of America and the law of the State of New York.

Asian Development Bank, p. 3

We are furnishing this opinion letter to you at the request of the Managers in our capacity as counsel to the Managers, and this letter is solely for your benefit. This opinion letter is not to be relied on by or furnished to any other person or used, circulated, quoted or otherwise referred to for any other purpose. Notwithstanding the foregoing, you may furnish a copy of this opinion letter (with notice to us, which shall be given before furnishing such copy, when practicable) (a) if required by any applicable law or regulation, (b) to any regulatory authority having jurisdiction over you if required by such authority or (c) in connection with any actual or threatened claim against you relating to the offering of the Notes if required to assist you in establishing defenses under applicable securities laws, it being understood and agreed that we assume no duty or liability whatsoever to any person furnished this letter in accordance with this sentence and that any such person is not entitled to rely on this letter in any manner as a result of being furnished this letter or for any other reason. We assume no obligation to advise you, or to make any investigations, as to any legal developments or factual matters arising subsequent to the date hereof that might affect the opinions expressed herein.