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

January 16, 2024

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 January 15, 2024 on the Hong Kong Stock Exchange’s website at:

https://www1.hkexnews.hk/listedco/listconews/sehk/2024/0115/2024011500550.pdf, in relation to the key operating data of the Company and its subsidiaries for December 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.

Date: January 16, 2024

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 December 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 December 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 December 2023, passenger capacity (measured by available seat kilometres (“ASK”)) of the Group increased by 149.76% 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 109.76%, 250.98% and 537.54%, 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 197.81%, of which, passenger traffic for domestic routes, regional routes and international routes increased by 151.39%, 522.05% and 650.32%, respectively, as compared with the same period last year. The passenger load factor was 79.38%, representing an increase of 12.81 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 13.27, 31.23 and 11.61 percentage points, respectively, as compared with the same period last year.

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In terms of cargo operations, in December 2023, cargo capacity (measured by available tonne kilometers (“ATK”)—Cargo and Mail) increased by 75.00% as compared with the same period last year. Cargo and mail traffic (measured by revenue tonne kilometres (“RTK”)—Cargo and Mail) increased by 43.56% as compared with the same period last year. The cargo and mail load factor was 52.14%, representing a decrease of 11.42 percentage points as compared with the same period last year.

In December 2023, the Group did not launch any new major route.

In December 2023, the Group introduced ten aircrafts (including four A321NEO aircrafts, five A320NEO aircrafts and one ARJ21 aircraft), and disposed of six aircrafts (including one A330-200 aircraft, two A321 aircrafts, two A320 aircrafts and one B737-700 aircraft). As of the end of December 2023, the Group operated a fleet of 908 commercial aircrafts as set out below:

KEY OPERATING DATA OF DECEMBER 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 January 2024

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

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