Marquis de Sade: Justine (Italian: Justine ovvero le disavventure della virtù, lit. 'Justine or the misadventures of virtue', also released as Deadly Sanctuary) is a 1969 erotic period drama film directed by Jesús Franco, written and produced by Harry Alan Towers, and based on the 1791 novel Justine by the Marquis de Sade. It stars Romina Power as the title character, with Maria Rohm, Klaus Kinski, Akim Tamiroff, Harald Leipnitz, Rosemary Dexter, Horst Frank, Sylva Koscina and Mercedes McCambridge.

The film is set in 1700s France where Justine (Power) and her sister Juliette (Rohm) are orphans in Paris. Juliette becomes a prostitute and marries a rich noble. Justine is falsely arrested and sentenced to death, then escapes from prison to become a fugitive.

The film was an international co-production between West Germany and Italy. Justine had Franco's largest budget to date, of just under a million dollars. Franco originally wanted to cast Rosemary Dexter as Justine, but was forced to cast Romina Power in the role, which led to Franco changing the story to suit her.