In addition to the 2020 Campeonato Brasileiro Série A, Flamengo also competed in the CONMEBOL Copa Libertadores, the Copa do Brasil, and the Campeonato Carioca, the top tier of Rio de Janeiro's state football league, Supercopa do Brasil and Recopa Sudamericana.

Supplier: Adidas / Sponsor: Banco BRB / Back of the shirt: MRV / Lower back: Total / Shoulder: Sportsbet.io / Numbers: TIM / Shorts: Azeite Royal / Socks: Orthopride Last updated: 25 February 2021 Source: Competitions Goals and red cards are shown.

The group stage draw for the 2020 Copa Libertadores was conducted on 17 December 2019.

Tied 2–2 on aggregate, Racing won on penalties and advanced to the quarter-finals Goals and red cards are shown.

Source: TheFinalBall Players in italics have left the club before the end of the season.