The 2021 Cork Premier Senior Football Championship was the second staging of the Cork Premier Senior Football Championship and the 133rd staging overall of a championship for the top-ranking Gaelic football teams in Cork. The draw for the group stage placings took place on 29 April 2021. The championship began on 20 July 2021 and ended on 28 November 2021.
Nemo Rangers entered the championship as the defending champions, however, they failed to make it out of the group stage after suffering two defeats. Ilen Rovers were relegated after being beaten by Carrigaline in a playoff.
The final was played on 28 November 2021 at Páirc UàChaoimh in Cork, between Clonakilty and St. Finbarr's, in what was their second ever final meeting and their first in 11 years. St. Finbarr's won the match by 0-14 to 0-13 to claim their tenth championship title overall and a first title since 2018.
Steven Sherlock was the championship's top scorer with 3-41.
Promoted from the Cork Senior A Football Championship
Relegated to the Cork Senior A Football Championship
The seedings were based on final group stage positions from the 2020 championship.