UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

Form 6-K

Report of Foreign Private Issuer

Pursuant to Rule 13a-16 or 15d-16

under the Securities Exchange Act of 1934

For the month of March 2026

Commission File Number: 001-42484

ASCENTAGE PHARMA GROUP INTERNATIONAL

(Translation of Registrant’s name into English)

68 Xinqing Road

Suzhou Industrial Park

Suzhou, Jiangsu

China

(Address of principal executive offices)

Indicate by check mark whether the registrant files or will file annual reports under cover of Form 20-F or Form 40-F.

Form 20-F ☒ Form 40-F ☐

EXPLANATORY NOTE

On March 17, 2026, Ascentage Pharma Group International issued a press releases entitled “Ascentage Pharma to Present Data From Four Preclinical Studies In Its Innovative Pipeline at American Association of Cancer Research (AACR) Annual Meeting 2026”. A copy of the press release is furnished as Exhibit 99.1. On March 18, 2026, Ascentage Pharma Group International issued an announcement entitled “Ascentage Pharma To Present Data From Four Preclinical Studies In Its Innovative Pipeline At American Association Of Cancer Research (AACR) Annual Meeting 2026”. A copy of the announcement is furnished as Exhibit 99.2.

INDEX TO EXHIBITS

SIGNATURE

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.