Born in Burletta, he studied the viola and conducting at the Academy of Santa Cecilia in Rome.
He worked at Milan Radio from 1946 to 1951, where he revived a number of obscure operas, including works by Alessandro Scarlatti. A production of Joseph Haydn's Il mondo della luna was heard by Arturo Toscanini and led to him recommending Giulini for the musical directorship at La Scala, where Giulini remained from 1953 to 1956. In 1958 he conducted a highly acclaimed production of Giuseppe Verdi's Don Carlo at the Royal Opera House, Covent Garden, but from 1967 he largely abandoned opera, concentrating on orchestral works. He conducted the Vienna Symphony Orchestra the Chicago Symphony Orchestra and the Philharmonia. From 1978 to 1984 he was principal conductor of the Los Angeles Philharmonic Orchestra. In 1982 he returned to opera, conducting Verdi's Falstaff.