My Bloody Valentine is a 1981 Canadian slasher film directed by George Mihalka from a screenplay by John Beaird. It features an ensemble cast that includes Paul Kelman, Lori Hallier, and Neil Affleck. The plot tells about a group of young adults who decide to throw a Valentine's Day party, only to incur the vengeful wrath of a maniac in mining gear who begins a killing spree.

Conceived and produced entirely over the course of around a year, the film was shot on location in Sydney Mines, Nova Scotia, in the fall of 1980. It was theatrically released in Canada on February 13, 1981 by Paramount Pictures Corporation, coinciding with the Valentine's holiday. Despite a mixed response from critics and grossing $5.7 million at the box office, the film has developed a large cult following over the years since its release.

My Bloody Valentine faced notable censorship, having a total of nine minutes cut by the Motion Picture Association of America due to the amount of violence and gore. Though co-producer Dunning confirmed that the excised footage still existed, attempts to release it proved difficult as Paramount Pictures refused to offer an uncut version. In 2009, Lionsgate subsequently licensed the home media rights to the film and released Blu-ray and DVD editions with three minutes of additional footage restored. The same year, Lionsgate released a remake of the film.