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 OF THE

SECURITIES EXCHANGE ACT OF 1934

For the month of September 2026

Commission File Number 001-41631

Xiao-I Corporation

(Translation of registrant’s name into English)

5F, Building 363

No. 1555 of West Jinshajiang Road

Shanghai, China, 201803

(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 ☐

INFORMATION CONTAINED IN THIS REPORT ON FORM 6-K

Semi-annual Report

Attached as Exhibit 99.1 to this Report are the Unaudited Condensed Consolidated Financial Statements of the Company as of June 30, 2026 and for the Six Months Ended June 30, 2026 and 2025, respectively, and the notes related thereto.

Attached as Exhibit 99.2 to this Report is the Operating and Financial Review and Prospects of the Company for the Six Months Ended June 30, 2026.

INCORPORATION BY REFERENCE

This Form 6-K and the exhibit to the Form 6-K, including any amendment and report filed for the purpose of updating such document, are incorporated by reference into the Company’s registration statements on Form S-8 (SEC File No. 333-275743), Form S-8 (333-286469), and Form F-3, as amended (SEC File No. 333-279306) (including any prospectuses forming part of such registration statements), and shall be a part thereof from the date on which this report is furnished, to the extent not superseded by documents or reports subsequently filed or furnished.

EXHIBIT INDEX

SIGNATURES

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.

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