Alexander Louis Theroux (born 1939) is an American novelist and poet whose best known novel is perhaps Darconville's Cat (1981) which was selected by Anthony Burgess’s Ninety-Nine Novels: The Best in English since 1939 – A Personal Choice in 1984 and in Larry McCaffery’s 20th Century’s Greatest Hits.He was awarded the Lannan Literary Award for Fiction in 1991 and the Clifton Fadiman Medal for Fiction in 2002 by the Mercantile Library in New York City.
He is the brother of novelist Paul Theroux and uncle of documentarian Louis Theroux and novelist Marcel Theroux.