Born in Rome, he began his career at four years of age with the 1956 film Supreme Confession.

[1] In that same year he performed the role of Paolo in Irvin Kershner's war film Face in the Rain.

[3][4] A later, popular acting role of his was that of Ciro, the newsagent, in the late '80s TV series I ragazzi della 3ª C.[3] As a voice actor, Giuliani became well known for providing the Italian voice of John Belushi in The Blues Brothers,[3] as well as Bugs Bunny (from 1996 to 2007, when the role was passed on to Davide Garbolino), Fozzie Bear in The Muppets and Buck from the Ice Age film series.

Giuliani has also dubbed Mel Gibson, Dudley Moore, Billy Crystal, John Candy, Andy García, Joe Pantoliano and Warwick Davis in some of their projects.

[5] In the early 2000s, Giuliani protested that he had been insulted and threatened by AS Roma supporters due to his impersonation of footballer Francesco Totti on the TV show Convenscion,[6] where he had also imitated other public figures such as sportspeople and politicians.