Night of the Demons (also known as: Halloween Party) is a 1988 cult classic horror film written and produced by Joe Augustyn and directed by Kevin S. Tenney. The film tells the story of ten high school seniors having a Halloween party in an isolated mortuary. Their party turns into a nightmare when after conducting a séance as a party game, they unlock the demon that remains locked in the crematorium. Filming of Night of the Demons took place in South Central Los Angeles, California, USA, and lasted for two months.

The film was extremely controversial for its graphic terror violence and gore, being initially turned down by almost all U.S. film distributors until a European company and International Film Marketing finally picked it up.[citation needed] It was finally released into theaters on October 14, 1988. Although its budget was just $1,200,000, the film was a moderate success at the box office, grossing a total of $3,109,904 in the U.S. upon its initial release. The film spawned two sequels, Night of the Demons 2 (1994) and Night of the Demons 3 (1997), and was remade in 2009. Linnea Quigley provided a cameo in the remake.

The film's gore was originally trimmed by the filmmakers to secure an R-rating for its theatrical exhibition. An unrated version, featuring the deleted violence, was released to video and is the version contained in Anchor Bay Entertainment's DVD.

It was given a limited theatrical release in the United States.