The defending champions were Rijeka, having won their sixth title the previous year by defeating Lokomotiva in the final.
[1] The following 48 teams qualified for the competition: The draw for the preliminary single-legged round was held on 25 August 2020 and the matches were played on 9 September 2020.
Teams in first round were paired by club coefficient and the matches were played on 7 October 2020.
16 and so on, with bigger numbers hosting a tie.
[5] Dinamo Zagreb v HNK Gorica has been postponed due to Dinamo's participation in the 2020–21 UEFA Europa League quarter finals.