Production notes

Ambler's novel is different from the film on several counts. The book is narrated by Simpson (named Arthur Abdel Simpson), so the reader only gradually comes to work out what Harper and his associates are really up to. Simpson in the book is blackmailed into driving the car to Istanbul after Harper catches him trying to steal Harper's travelers' checks. The book features frequent flashbacks to Simpson's schooldays in England, which help to explain his character and motives more clearly than in the film. According to Jules Dassin, he originally planned to cast Peter Sellers as Simpson, but Sellers refused to work with Maximilian Schell, who he claimed had a reputation for being difficult. Dassin was not prepared to dispense with Schell, and so cast Ustinov in place of Sellers. Ustinov won the Academy Award for Best Supporting Actor for his portrayal of Simpson. It was his second win in the category, having won four years previously for his work in Spartacus. Appearing in supporting roles were Gilles Ségal as the "Human Fly" and Joe Dassin as Joseph, who runs the traveling fair display that is supposed to smuggle the dagger out of Turkey. The athletic Ségal later inspired other "trickwire" stunts, including a few used for the Mission: Impossible television series and film. Joe Dassin was the son of the film's director Jules Dassin, and appeared as an actor in a handful of films, but was better known as a singer-songwriter. Principal photography began on August 12, 1963. The majority of location filming was completed in Istanbul, Turkey, with locations including the Topkapı Palace, Hagia Sophia, the Bosporus waterway dividing Europe and Asia, the Golden Horn, the Sea of Marmara, and Dolmabahçe Palace, before moving for one week of shooting at the harbor of Kavala, Greece. Interiors were shot at the Billancourt Studios in Paris.

Topkapi grossed $7 million at the US box office, earning $4 million in theatrical rentals in the United States and Canada.

On the review aggregator website Rotten Tomatoes, the film holds an approval rating of 95% based on 21 reviews, with an average rating of 7.8/10.

Bosley Crowther of The New York Times applauded the film as well acted, "adroitly plotted", and abounding in brilliant Technicolor that Dassin exploits "like a child with a new paint box", but he saved his greatest praise for Ustinov:[I]t is his misadventures and confusions and frights that truly make this picture something more than melodrama with a farcical edge. He makes it a joyous sort of travesty of the bad art of burglary. To see Mr. Ustinov sweating through his mischance encounters with the Turkish police, or playing the role of stool pigeon while running with the gang, or climbing about the roof of the palace under the heavy influence of vertigo, with the Golden Horn in the distance, is to see first-class comedy.

Topkapi later inspired the Mission: Impossible television series, and the scene in which a character hangs by a rope in order to steal a dagger inspired a similar scene in the 1996 Mission: Impossible film, where Ethan Hunt (Tom Cruise) rappels into a secure room to access a computer. In his 2007 autobiography, Peter Sallis, who voiced Wallace, said the 1993 short film The Wrong Trousers was based loosely on Topkapi, and said it was his favorite Wallace & Gromit film.