William Degouve de Nuncques, February 28, 1867–March 1, 1935, was a Belgian painter born in Monthermé, France. His family settled in Brussels in 1874. After briefly attending the art academy in Ixelles, he developed largely through independent study. Jan Toorop and Henry de Groux were important early associates, and he shared a studio with de Groux.

He exhibited as a guest at the final Les XX exhibition in 1893 and subsequently at La Libre Esthétique. In 1894 he married the painter Juliette Massin, whose sister was married to Émile Verhaeren. His work included Symbolist nocturnes in oil and pastel, Mediterranean landscapes painted during his stay in Mallorca from 1899 to 1902, and Belgian winter landscapes.

After living in the Netherlands during the First World War, he returned to Belgium in 1919. Following Massin’s death that year, he stopped painting for several years. He later settled in Stavelot, where he died. His works are held by the Kröller-Müller Museum, the Royal Museums of Fine Arts of Belgium, Musée d’Orsay, and Centraal Museum.