Clive Revill made his Broadway debut in 1952, playing Mr. Pickwick in The Pickwick Papers and subsequently appeared in Irma La Douce, The Incomparable Max, and Oliver!, for which his Fagin was nominated for a Tony Award. He is also known for his roles in the operettas of Gilbert and Sullivan, on both stage and television. He starred in the first national tour of the musical Drood, replacing George Rose, who was murdered during the run. He also participated in the workshop production of Tom Jones: The Musical, playing the role of Squire Western and reprising it on the cast recording.

His red hair and distinctive Mr. Punch-like features often saw him cast as comic eccentrics in a number of British films of the 1960s and 1970s such as Kaleidoscope (1966), Modesty Blaise (1966), Fathom (1967), The Assassination Bureau (1969), and One of Our Dinosaurs Is Missing (1975). He also had notable supporting turns in Otto Preminger's Bunny Lake Is Missing (1965) opposite Laurence Olivier, Mack the Knife (1989), and his American film debut A Fine Madness (1966), as well as a leading role in the horror film The Legend of Hell House (1973).

He was often cast as humorous foreign characters (he has played everything from Chinese to Russian). Two of his highest profile roles of this kind were in two films for Billy Wilder: The Private Life of Sherlock Holmes (1970) and Avanti! (1972), for which he was nominated for a Golden Globe Award for his part as put-upon hotel manager Carlo Carlucci. In the 1979 television miniseries Centennial, he played the Scottish accountant Finlay Perkin. He played both Ko-Ko (the starring role) in The Mikado, and the title character, John Wellington Wells, in The Sorcerer for the Brent Walker television series of Gilbert and Sullivan productions, shown by the BBC in 1983.

After relocating to the United States, he guest-starred in many television series, such as Columbo, Hart to Hart, Dynasty, Magnum, P.I., The Love Boat, Remington Steele, Murder, She Wrote, Babylon 5, The Feather and Father Gang, Newhart, MacGyver, Dear John, The Fall Guy, Maude, and Star Trek: The Next Generation. He also starred as the wizard Vector in the short-lived cult series Wizards and Warriors and voiced Alfred Pennyworth in the first three episodes of Batman: The Animated Series.

To Star Wars fans, he is best known as the original Emperor Palpatine in The Empire Strikes Back.  He is also known for his voice work, which in addition to Batman: The Animated Series includes numerous cartoons such as Transformers and Duck Tales as well as video games such as Marvel: Ultimate Alliance and Conquest: Frontier Wars.