Original New Balance trainingsshirt Celtic 2019/20

The 2019–20 season was Celtic's 131st season of competitive football. They competed in the Scottish Premiership, League Cup, Scottish Cup, Champions League and Europa League. Celtic won all three domestic tournaments, completing an unprecedented quadruple treble.

On 13 March 2020, the Scottish football season was suspended with immediate effect due to the COVID-19 pandemic. The season was curtailed as a result, with Celtic declared Scottish Premiership champions on 18 May, winning a ninth consecutive league title.