Cited by Mission: Impossible (1966) series creator Bruce Geller as the inspiration for his own series.
The title refers to the Topkapi Palace built by the Ottoman Sultan Mehmed II in 1459 after the fall of the Byzantine Empire. The Ottoman sultans made the Topkapi palace their main residence for 400 years. It became a museum in 1924, and its hundreds of rooms contain numerous collections of historical and religious relics, treasures, and jewelry. Topkapi means literally "Cannon Gate" in Turkish.
Turkish authorities reviewed the script and monitored this production as a previous Hollywood film had cast the country in a negative light, according to a contemporary article in the Los Angeles Times. Director Jules Dassin also had to shoot the robbery in such a way as to not compromise the security of the real museum where filming took place.
Director Jules Dassin went on to marry female lead Melina Mercouri a couple years after this film was released and they remained married until her passing in 1994.
Director Jules Dassin originally planned to cast Peter Sellers as Arthur Simon Simpson and hoped to cast Orson Welles as Cedric Page. Welles refused this role, and Sellers later dropped out after the start of production was delayed from May to August, to be replaced by Sir Peter Ustinov (whom Sellers had replaced in The Pink Panther (1963)).