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

February 16, 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 February 15, 2023 on the Hong Kong Stock Exchange’s website at:

https://www1.hkexnews.hk/listedco/listconews/sehk/2023/0215/2023021500371.pdf, in relation to the key operating data of the Company and its subsidiaries for January 2023.

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: February 16, 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.

(a joint stock limited company incorporated in the People’s Republic of China with limited liability)

(Stock Code: 1055)

ANNOUNCEMENT ON KEY OPERATING DATA

This announcement is made based on the operating data for January 2023 of the Group to be published on the Shanghai Stock Exchange, and pursuant to Rules 13.09 and 13.10B of the Listing Rules and the Inside Information Provisions (as defined in the Listing Rules) under Part XIVA of the Securities and Futures Ordinance (Chapter 571 of the Laws of Hong Kong).

The relevant key operating data was calculated based on the internal statistics of the Group, which may differ from the data disclosed in the relevant periodic reports. Investors are hereby reminded of the risks which may result from inappropriate reliance upon or utilization of the relevant information.

This announcement is made based on the operating data for January 2023 of China Southern Airlines Company Limited (the “Company”) and its subsidiaries (collectively, the “Group”) to be published on the Shanghai Stock Exchange, and pursuant to Rules 13.09 and 13.10B of the Rules Governing the Listing of Securities on The Stock Exchange of Hong Kong Limited (the “Listing Rules”) and the Inside Information Provisions (as defined in the Listing Rules) under Part XIVA of the Securities and Futures Ordinance (Chapter 571 of the Laws of Hong Kong).

In January 2023, passenger capacity (measured by available seat kilometres (“ASK”)) of the Group increased by 25.41% as compared with the same period last year (a year-on-year (“YoY”) basis), of which, passenger capacity for domestic routes, regional routes and international routes increased by 22.08%, 284.01% and 114.26%, respectively, as compared with the same period last year. Compared with the same period last year, passenger traffic (measured by revenue passenger kilometres (“RPK”)) increased by 44.62%, of which, passenger traffic for domestic routes, regional routes and international routes increased by 40.01%, 585.78% and 198.71%, respectively, as compared with the same period last year. The passenger load factor was 72.67%, representing an increase of 9.65 percentage points as compared with the same period last year, of which, the passenger load factor for domestic routes, regional routes and international routes increased by 9.32, 27.20 and 20.47 percentage points, respectively, as compared with the same period last year.

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In terms of cargo operations, in January 2023, cargo capacity (measured by available tonne kilometers (“ATK”) - Cargo and Mail) increased by 6.74% as compared with the same period last year. Cargo and mail traffic (measured by revenue tonne kilometres (“RTK”) - Cargo and Mail) decreased by 10.22% as compared with the same period last year. The cargo and mail load factor was 46.20%, representing a decrease of 8.73 percentage points as compared with the same period last year.

In January 2023, the Group has newly launched the following major route: Yinchuan-Shenyang-Yinchuan (being seven flights a week).

In January 2023, the Group disposed of two A380 aircrafts. As of the end of January 2023, the Group operated a fleet of 892 commercial aircrafts as set out below:

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KEY OPERATING DATA OF JANUARY 2023

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Notes:

The key operating data above was calculated based on the internal preliminary statistics of the Group, which may be subsequently adjusted or differ from the data disclosed in the relevant periodic reports. Investors are hereby reminded of the risks which may result from inappropriate reliance upon or utilization of the information given above.

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Guangzhou, the People’s Republic of China

15 February 2023

As at the date of this announcement,the Directors 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 independentnon-executive Directors.

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