Edouard Léon Théodore Mesens was a Belgian artist and writer associated with the Belgian Surrealist movement. Edouard Léon Théodore Mesens was born in Brussels, Belgium.

He started his artistic career as a musician influenced by Erik Satie and an author of dadaist poems. He was a publisher of the books Œesophage and Marie, both with his lifetime friend and soulmate René Magritte. His activity as one of the leaders of the surrealist movement in Belgium was eased by the fact that he was an owner of a gallery, where he organised the first surrealist exhibition in Belgium in 1934 . As its organiser, he also went to co-organise the London International Surrealist Exhibition which made him settle down in London. There he became the director of the London Gallery (which he ran during the late 30s and after the war with Roland Penrose) and the chief editor of the London Bulletin (1938–1940) - which was one of the most important bulletins among the English-language Surrealist periodicals.

Mesens died early in 1971 following a "long, lingering, painful illness." According to a thoughtful and sympathetic obituary published by poet and historian Franklin Rosemont, Mesens committed "suicide by absinthe," drinking himself to death by willfully disregarding doctors' orders to abstain completely from alcohol.