The Sinner () is a 1975 Italian romantic drama film co-written and directed by Pier Ludovico Pavoni.
The film was a produced by P.A.C. It was the last film of Clara Calamai and the last film directed by Pavoni.
Italian film critic Marco Giusti described the film as "remarkable", a "curious Matarazzata with a fine cast and a Zeudi Araya at her best". Antonio Guastella from Nocturno described it as a "turgidly retro" and more socially engaged variation of Pavoni's previous effort Amore libero - Free Love. He wrote "Interesting in the beginning [...] it loses its way in the second half, becoming rushed and sluggish, despite its excellent sets and a particularly evocative music interspersed with singer-songwriter Rosa Balistreri's voice". According to Paolo Mereghetti, the film is midway between art cinema and fotoromanzo, with too many stereotypes about the fatalism, attitude, and immobility of Sicily.