The 2020–21 season was the 122nd season in existence of Cardiff City Football Club. In addition to the Championship, Cardiff City participated in that season's editions of the FA Cup, the Welsh League Cup, and participated in the EFL Cup.
 "As of 8 May 2021"
First-team squad.
Note: Flags indicate national team as has been defined under FIFA eligibility rules. Players may hold more than one non-FIFA nationality.
 "As of 8 May 2021"
Players with names "in italics" and marked * were on loan from another club for the whole of their season with Cardiff City.
 "As of 8 May 2021"
 "As of 8 May 2021"
 "As of 8 May 2021"
Statistics.
Clean sheets.
"Includes all competitive matches. The list is sorted by squad number when total clean sheets are equal. Numbers in parentheses represent games where both goalkeepers participated and both kept a clean sheet; the number in parentheses is awarded to the goalkeeper who was substituted on, whilst a full clean sheet is awarded to the goalkeeper who was on the field at the start of play. "
 "As of match played 7 May 2021"
Pre-season and friendlies.
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Competitions.
EFL Championship.
Matches.
The 2020–21 season fixtures were released on 21 August.
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FA Cup.
The third round draw was made on 30 November, with Premier League and EFL Championship clubs all entering the competition.
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EFL Cup.
The first round draw was made on 18 August, live on Sky Sports, by Paul Merson.
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Welsh League Cup.
Cardiff entered the Welsh League Cup for the first time in the club's history in the 2020–21 season.
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Club staff.
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References.
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