Mark Haddon (born on September 26, 1962 in Northampton) is a British novelist and poet, best known for his 2003 novel The Curious Incident of the Dog in the Night-time.

Haddon was educated at Uppingham School and Merton College, Oxford, where he studied English.

In 2003, Haddon won the Whitbread Book of the Year Award and in 2004, the Commonwealth Writers' Prize Overall Best First Book for his novel The Curious Incident of the Dog in the Night-time, a book which is written from the perspective of a boy with Aspergers syndrome. Haddon's knowledge of Aspergers syndrome, a type of autism, comes from his work with autistic people as a young man. In an interview at Powells.com, Haddon claimed that this was the first book that he wrote intentionally for an adult audience; he was surprised when his publisher suggested marketing it to both adult and child audiences. His second adult-novel, A Spot of Bother, was published in September 2006.