Calamity of Snakes (人蛇大战; Ren she da zhan) is a 1982 horror film directed by Chi Chang (also known as William Cheung Kei).

An international co-production of Taiwan and Hong Kong, the film concerns the residents of a newly built apartment building being attacked by thousands of vengeful snakes, which seek retribution for the killing and displacement of multitudes of snakes at the site of the building's construction.

[1] The film was banned in British Columbia, Canada, by the British Columbia Film Classification Branch in 1982.

[2] In 2023, Jeffrey Kauffman of Blu-ray.com called the film "a completely gonzo outing that has a few scattered moments of humor which are probably completely undercut (no pun intended) by the absolutely horrifying footage of snakes being killed in various ways.

"[3] In April 2023, Unearthed Films released Calamity of Snakes on Blu-ray and DVD;[3][4] the release includes a "cruelty free version" of the film which omits shots that feature snakes being harmed.