6-K

UNITEDSTATES

SECURITIESAND EXCHANGE COMMISSION

WASHINGTON,D.C. 20549

FORM6-K

REPORTOF FOREIGN PRIVATE ISSUER

PURSUANTTO RULE 13a-16 OR 15d-16

UNDERTHE SECURITIES EXCHANGE ACT OF 1934

For the month of November 2025

Commission File Number: 001-38146

ZKINTERNATIONAL GROUP CO., LTD.

(Exact name of registrant as specified in its charter)

c/oZhejiang Zhengkang Industrial Co., Ltd.

No.678 Dingxiang Road, Binhai Industrial Park

Economic& Technology Development Zone

Wenzhou,Zhejiang Province

People’sRepublic of China 325025

(Address of principal executive office)

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 ☐

Informationcontained in this form 6-K report

As previously reported, On October 20, 2025, ZK International Group Co., Ltd. (the “Company”) entered into a securities purchase agreement (the “Purchase Agreement”) with certain Non-U.S. investors (collectively, the “Purchasers”) pursuant to which the Company agreed to sell to the Purchasers an aggregate of 10,010,000 ordinary shares, no par value per share (the “Ordinary Shares”), of the Company at a price of $2.09 per share.

The transaction closed on November 14, 2025 where the Company issued an aggregate of 10,010,000 Ordinary Shares for an aggregate consideration of $20,920,900.

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SIGNATURES

Pursuant to the requirements of the Securities and 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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