6-K

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON D.C. 20549

FORM 6-K

Report ofForeign Private Issuer

Pursuant to Rule 13a-16 or15d-16

of the Securities Exchange Act of 1934

March 31, 2023

CHINASOUTHERN AIRLINES COMPANY LIMITED

68 Qi Xin Road

Guangzhou, 510403

People’s Republic of China

(Address of principal executive offices)

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  ☐

China Southern Airlines Company Limited (the “Company”) published the following announcement on March 30, 2023 on the Hong Kong Stock Exchange’s website at:

https://www1.hkexnews.hk/listedco/listconews/sehk/2023/0330/2023033001148.pdf, in relation to the closure of register of holders of H shares.

The announcement in English is included as an exhibit to this Form 6-K.

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.

CHINA SOUTHERN AIRLINES COMPANY LIMITED

Date: March 31, 2023

EX-99.1

Exhibit 99.1

Hong Kong Exchanges and Clearing Limited and The Stock Exchange of Hong Kong Limited take no responsibility for the contents of this announcement, make norepresentation as to its accuracy or completeness and expressly disclaim any liability whatsoever for any loss howsoever arising from or in reliance upon the whole or any part of the contents of this announcement.

CLOSURE OF REGISTER OF HOLDERS OF H SHARES

An extraordinary general meeting (the “EGM”) of China Southern Airlines Company Limited will be convened and held on Friday, 19 May 2023. A circular in respect of the EGM containing details of the resolution(s) to be proposed at the EGM, together with the notice of the EGM, will be dispatched to the shareholders of the Company in due course.

For the purpose of ascertaining the entitlement of the holders of H shares of the Company who are eligible to attend and vote at the EGM, the register of holders of H shares of the Company will be closed from Wednesday, 19 April 2023 to Friday, 19 May 2023 (both days inclusive). In order to qualify for attending the EGM, all transfer documents of H Shares together with the relevant share certificates must have been lodged with the Company’s H share registrar and transfer office in Hong Kong, Hong Kong Registrars Limited, at 17M Floor, Hopewell Centre, 183 Queen’s Road East, Wanchai, Hong Kong, not later than 4:30 p.m. on Tuesday, 18 April 2023 for registration.

Guangzhou, the People’s Republic of China

30 March 2023

As at the date of this announcement, theDirectors include Ma Xu Lun, Han Wen Sheng and Luo Lai Jun as executive Directors; and Liu Chang Le, Gu Hui Zhong, Guo Wei and Cai Hong Ping as independent non-executive Directors.

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