The Lerner and Loewe musical will open Aug. 14 following previews beginning Aug. 6.
Topol is best known for his stage and screen performances as Tevye in the musical Fiddler of the Roof. In Gigi he will play the role of Honoré, played by Maurice Chevalier in the 1958 movie.
The revival will be directed by the Open Air's new artistic director Timothy Shaeder and will feature Millicent Martin in the role of Inez Alvarez and Lisa O'Hare (title role of London's Mary Poppins and the U.S. touring version of My Fair Lady) in the role of Gigi.
The show, which features the songs "Thank Heaven For Little Girls" and "I Remember It Well," has not been seen in London since John Dexter's 1985 production at the West End's Lyric Theatre. Shaeder's version will be choreographed by Stephen Mear (The Little Mermaid and Mary Poppins).
Martin made regular appearances on the hit TV shows "Will & Grace" and "Frasier." But her singing talents first came to the fore in the 1960s groundbreaking television satire "That Was The Week That Was." Her stage credits also include Side by Side Sondheim.
For the first time the Open Air's will also feature a third Shakespeare play — a reworked 70-minute version of A Midsummer Night's Dream especially produced for a young audience. The shortened version officially opens on July 12 following previews beginning July 8.
For more on the Open Air Theatre's season call 0844 826 4242 or visit www.openairtheatre.org.