The 2020–21 NK Istra 1961 season was the club's 60th season in existence and the 12th consecutive season in the top flight of Croatian football.

Note: Flags indicate national team as defined under FIFA eligibility rules; some limited exceptions apply.

Players may hold more than one non-FIFA nationality.

Source: Glasilo Hrvatskog nogometnog saveza Source: Glasilo Hrvatskog nogometnog saveza Total spending: 0 € Total income: 122,000 € Total expenditure: 122,000 € Last updated: 23 May 2021 Source: Soccerway Last updated: 23 May 2021.

Source: Prva HNL Source: Croatian Football Federation Source: Croatian Football Federation[28] Updated 23 May 2021 Source: Competitive matches Source: Competitive matches