The regular season ran from 26 April to 9 November 2021 (originally until 5 October, but was delayed because of the COVID-19 pandemic in South Korea).
[1] Due to the COVID-19 pandemic, the total amount of rounds were reduced from 28 to 21 (same as the previous season).
[2] The total number of foreign players was restricted to three per club, including a slot for a player from the Asian Football Confederation countries.
Boeun Sangmu were not allowed to sign any foreign players due to their military status.
Incheon Hyundai Steel Red Angels won 2–1 on aggregate.