The 2021 China League One () is the 18th season of the China League One, the second tier of the Chinese football league pyramid, since its establishment in 2004.
The 2021 China League One season was scheduled to start on 17 March 2021, but later was postponed.
On 1 April, the Chinese Football Association announced that the season would start on 24 April 2021 and the format of the season. The season was divided into 4 stages (10, 8, 8 and 8 rounds respectively). In the first stage, 18 teams were divided into 3 groups based on the hosts and last season's rankings. In the second, third and fourth stage, the teams in 3 groups will be switched to ensure that each team can play against each other 2 times.
The draw for the stages took place on 1 April 2021.
Teams promoted from 2020 China League Two
Teams promoted to 2021 Chinese Super League
Dissolved entries
Ahead of the 2021 season, the Chinese Football Association ordered all clubs to eliminate any corporate references in their names.
The number of foreign players clubs can register over the course of the season is limited to four and the number of foreign players allowed on each team at any given time is limited to three. A maximum of three foreign players can be registered for each match with a maximum of two can be fielded at any time during the match. In addition, each club can register a Hong Kong, Macau, or Taiwan player of Chinese descent (excluding goalkeepers), provided that he registered as a professional footballer in one of those three association for the first time, as a native player.
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Zhejiang and Chengdu Rongcheng will play the bottom two teams in the 2021 Chinese Super League (7th and 8th in the Relegation stage) in two-legged playoffs.
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2âÂÂ2 on aggregate. Qingdao Youth Island won 5âÂÂ4 on penalties.
Guangxi Pingguo Haliao won 1âÂÂ0 on aggregate.