The 1984–85 season was Sport Lisboa e Benfica's 81st season in existence and the club's 51st consecutive season in the top flight of Portuguese football, covering the period from 1 July 1984 to 30 June 1985. Benfica competed domestically in the Primeira Divisão, and the Supertaça Cândido de Oliveira, and participated in the European Cup after winning the previous league.