The 2020–21 season is Port's 4th consecutive seasons in top flight after promoted back from Thai League 2 in 2017.

Also, as Port won the 2019 Thai FA Cup, they are qualified to the preliminary round 2 of 2020 AFC Champions League.

In this season, Port participates in 4 competitions which consisted of the Champions Cup, Thai League, FA Cup, and AFC Champions League.

[1] However, on March 4, the decision changed to postpone all of matches prior to 18 April due to the coronavirus pandemic in Thailand.

[2] It was later confirmed that the match will be restarted in September 2020 and end in May 2021.