Leontine Sagan (born Leontine Schlesinger, 1889 in Vienna, Austria, died 1974 in South Africa) was a German actress.

Starting her careers as an actress and theatre producer, Sagan trained with Max Reinhardt. She later became a radical lesbian film-maker during the Weimar Republic in Germany.

Her best-known film is Madchen in Uniform (1931). It had an all-female cast and featured Erika Mann in a leading role. The film was ground-breaking not only for its portrayal of lesbian and pedagogic eros , but also for its co-operative and profit-sharing financial arrangements. An alternate ending, which pandered to pro-Nazi ideals, enabled the film to be screened in Germany, but eventually even this version of the film was banned as 'decadent' by the Nazi regime. Sagan fled Germany soon after her film was banned.

Sagan worked on films with Alexander Korda in England, but then moved to South Africa and founded the National Theatre of Johannesburg .

The film Mädchen in Uniform, based on the novel by Christa Winsloe, survived. But it was much-censored until the 1970s. Eleanor Roosevelt is credited with helping to revoke its censorship in the USA. It was recently released in its surviving form as a video-tape - with English subtitles - in the USA in 1994 and in the UK in 2000. Even this version probably lacks sections that were in the original - for a full understanding of what may have been censored, viewing the film is best followed by reading the original novel by Christa Winsloe.