Jazz on a Summer's Day is a 1959 concert film set at the 1958 Newport Jazz Festival in Newport, Rhode Island (which took place from July 3 to July 6 of 1958). The film was directed by commercial and fashion photographer Bert Stern and Aram Avakian, who also edited the film. The Columbia Records jazz producer, George Avakian, was the musical director of the film.

The film mixes images of water and the city with the performers and audience at the festival. It also features scenes of the 1958 America's Cup yacht races. The film is largely without dialog or narration (except for periodic announcements by emcee Willis Conover).

The film features performances by Jimmy Giuffre; Thelonious Monk; Sonny Stitt; Anita O'Day; Dinah Washington; Gerry Mulligan; Chuck Berry; Chico Hamilton, with Eric Dolphy; and Louis Armstrong, with Jack Teagarden. Also appearing are Buck Clayton, Jo Jones, Armando Peraza, and Eli's Chosen Six, the Yale College student ensemble that included trombonist Roswell Rudd, shown driving around Newport in a convertible jalopy, playing Dixieland.As was scheduled in advance and announced in the program, the last performer Saturday night was Mahalia Jackson, who sang a one-hour program beginning at midnight, thus ushering in Sunday morning. The film concluded with her performance of The Lord's Prayer.

In 1999, the film was selected for preservation in the United States National Film Registry by the Library of Congress as being "culturally, historically, or aesthetically significant". The film received a 100% score on Rotten Tomatoes.