Born in Venice, Polacco started his career in 1920 in the stage company of Emilio Zago, with whom he played most of the Goldoni's repertoire.

[1] Being of Jewish origin, he was temporarily forced to abandon acting because of the 1938 Fascist racial laws, resuming his activities at the end of the war, in 1945.

[1] Also active on radio and television, he got a large popularity thanks to the Inspector Rock character he played in Carosello, in a series of giallo-comedy shorts aired between 1957 and 1968.

[1][2] Polacco was also a voice actor, having dubbed a number of actors which include Ward Bond, Anthony Quinn, Chill Wills, Howard da Silva, Louis Calhern, Richard Boone and Boris Karloff in several of their films.

In his animated roles, he provided the Italian voice of Happy in Snow White and the Seven Dwarfs as well as one of the crows in Dumbo.