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

August 17, 2021

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  ☐

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):  ☐

Indicate by check mark whether the registrant by furnishing the information contained in this Form is also thereby furnishing the information to the Commission pursuant to Rule 12g3-2(b) under the Securities Exchange Act of 1934.

Yes  ☐            No  ☒

If “Yes” is marked, indicate below the file number assigned to the registrant in connection with Rule 12g3-2(b):   N/A

China Southern Airlines Company Limited (the “Company”) published the following announcement on August 16, 2021 on the Hong Kong Stock Exchange’s website at:

https://www1.hkexnews.hk/listedco/listconews/sehk/2021/0816/2021081600321.pdf, in relation to the key operating data of the Company and its subsidiaries for July 2021.

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: August 17, 2021

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 limitedliability)

(Stock Code: 1055)

ANNOUNCEMENT ON KEY OPERATING DATA

This announcement is made based on the operating data for July 2021 of the Group to be published on the Shanghai Stock Exchange and pursuant to Part XIVA of the Securities and Futures Ordinance.

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 July 2021 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 Part XIVA of the Securities and Futures Ordinance.

In July 2021, passenger capacity (measured by available seat kilometres (“ASK”)) of the Group increased by 25.27% as compared with the same period last year (a year-on-year (“YoY”) basis), of which, passenger capacity for domestic, regional and international routes increased by 25.65%, 162.46% and 10.32%, 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 32.19%, of which, passenger traffic for domestic and regional routes increased by 33.17% and 161.98%, respectively, while that for international routes decreased by 2.99%, as compared with the same period last year. The passenger load factor was 76.53%, representing an increase of 4.00 percentage points as compared with the same period last year, of which, the passenger load factor for domestic increased by 4.37 percentage points, while that for regional routes and international routes decreased by 0.06 percentage points and 7.46 percentage points, respectively, as compared with the same period last year.

In terms of cargo operations, in July 2021, cargo capacity (measured by available tonne kilometers (“ATK”)—Cargo and Mail) decreased by 1.40% as compared with the same period last year. Cargo and mail traffic (measured by revenue tonne kilometres (“RTK”)—Cargo and Mail) decreased by 2.29% as compared with the same period last year. The cargo and mail load factor was 48.86%, representing a decrease of 0.44 percentage points as compared with the same period last year.

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In July 2021, the Group has newly launched the following major routes: Beijing Daxing – Nanchang – Beijing Daxing, Zhuhai – Guiyang – Zhuhai (each being seven flights a week).

In July 2021, the Group introduced one aircraft (A321NEO), and disposed of one aircraft (A330-300). As of the end of July 2021, the Group operated a fleet of 869 aircrafts as set out below:

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KEY OPERATING DATA OF JULY 2021

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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

16 August 2021

As at the date of this announcement, theDirectors include Ma Xu Lun and Han Wen Sheng as executive Directors; and Liu Chang Le, Gu Hui Zhong, Guo Wei and Yan Andrew Y as independent non-executive Directors.

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