[3] Ulsan Hyundai won their second Champions League title by defeating Persepolis 2–1 in the final.

[4] Ulsan automatically qualify for the 2021 AFC Champions League (although they had already qualified through their domestic performance), the first time since 2008 that the AFC Champions League holders were guaranteed automatic qualification in the following year.

[7] The competition was suspended due to the COVID-19 pandemic in Asia after group stage matches on 4 March 2020,[8] and restarted on 14 September 2020.

Extra time and a penalty shoot-out were used to decide the winner if necessary (Regulations Article 9.2).

All losers in each round from associations with only play-off slots entered the AFC Cup group stage.

The draw for the group stage was held on 10 December 2019, 16:30 MYT (UTC+8), at the AFC House in Kuala Lumpur, Malaysia.

Each tie was played as a single-leg match at centralised venues, instead of the usual home-and-away two-legged basis as planned before the COVID-19 pandemic.

[12] Note: Abderrazak Hamdallah finished ahead of Júnior Negrão to win the Top Scorer award despite scoring the same number of goals, and also having the same number of assists (first tiebreaker), since he played fewer minutes throughout the competition (second tiebreaker).

Note: Goals scored in the qualifying play-offs and matches voided by AFC are not counted when determining top scorer (Regulations Article 64.4).