From 1937 until 1961, he wrote up to 100 film scores and won three academy awards for Spellbound, A Double Life and the monumental film epic Ben-Hur. Amongst various other directors, Rózsa also collaborated with Billy Wilder for five movies.

His most famous student was Jerry Goldsmith, who later also gained fame as a film composer. Although working in Hollywood for several decades, including 14 years for MGM, Rózsa also wrote orchestral and chamber works for the concert hall, which were performed by conductors like Bruno Walter, Leonard Bernstein and André Previn and soloists like Jascha Heifetz, leading to recognition both in the world of film and concert music.