The Black Sleep is a 1956 American independent horror film directed by Reginald LeBorg, and written by John C. Higgins from a story by Gerald Drayson Adams. It stars Basil Rathbone, Lon Chaney Jr., John Carradine, Bela Lugosi, and Akim Tamiroff. Tor Johnson appears in a supporting role. The film was produced by Aubrey Schenck and Howard W. Koch, as part of a four-picture finance-for-distribution arrangement with United Artists.

The film marked Bela Lugosi's last complete role before his death in August 1956, although some scenes featuring Lugosi were later included in Ed Wood's Plan 9 from Outer Space (in which Tor Johnson also appears), completed in 1957 but not released for distribution until 1959.The film was released as a double feature with the 1955 British film The Creeping Unknown (the title of the American release of the British film The Quatermass Xperiment). The Black Sleep was re-released in 1962 under the title Dr. Cadman's Secret.