Homicidal is a 1961 American horror-thriller film produced and directed by William Castle, and starring Glenn Corbett, Patricia Breslin, Eugenie Leontovich, Alan Bunce and Jean Arless. The film follows a murderous woman in a small California town whose presence unearths secrets concerning a prominent local family.

As with many of Castle's films, the film was released with a promotional gimmick—in this case, a "fright break," that allowed patrons to receive a refund if they were too scared to stay for the climax of the film. While a few reviews upon its release were mixed, it has since gained a cult following and is considered one of Castle's best films.