Under the Volcano is a novel by English writer Malcolm Lowry (1909–1957) published in 1947. The novel tells the story of Geoffrey Firmin, an alcoholic British consul in the Mexican city of Quauhnahuac, on the Day of the Dead in November 1938. The book takes its name from the two volcanoes, Popocatepetl and Iztaccihuatl, that overshadow Quauhnahuac and the characters. Under the Volcano was Lowry's second and last complete novel.

Clarence Malcolm Lowry was an English poet and novelist who is best known for his 1947 novel Under the Volcano, which was voted No. 11 in the Modern Library 100 Best Novels list.