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 May 2019

Commission Filing Number: 001-38205

ZAI LAB LIMITED

(Translation of registrant’s name into English)

4560 Jinke Road, Bldg. 1, 4F, Pudong, Shanghai, China 201210

(Address of principal executive office)

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

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(1): ☐

Indicate by check mark if the registrant is submitting the Form 6-K in paper as permitted by Regulation S-T Rule 101(b)(7): ☐

EXPLANATORY NOTE

The document attached as exhibit 1.1 to this Current Report on Form 6-K is hereby incorporated by reference into the Registration Statement on Form F-3 of Zai Lab Limited (File No. 333-230630).

SIGNATURES

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

ZAI LAB LIMITED
By:	/s/ Billy Cho
Name:	Billy Cho
Title:	Chief Financial Officer

Date: May 2, 2019

EXHIBIT INDEX

Exhibit No.	Description
1.1	Form of underwriting agreement