Born in Tropea, Calabria, the son of a Lawyer, Vallone attended Liceo classico Cavour in Turin, and studied Law and Philosophy at the University of Turin and entered his father's law firm. He played professional football at a young age, playing in Serie A for Torino. He won the Coppa Italia with his team in season 1935–1936. He subsequently became the editorial head of the culture section of L'Unità, then the official newspaper of the Italian Communist Party, and also a film and drama critic for the Turin newspaper La Stampa. During World War II, Vallone served with the Communist resistance.