Edouard Agneessens (24 August 1842, Brussels – 20 August 1885, Uccle) was a Belgian painter born in Brussels. He studied under Jean-François Portaels from 1859 at the Académie Royale des Beaux-Arts in Brussels, and in 1869 won the Prix de Rome. In 1868, he was one of the founding members of the Société Libre des Beaux-Arts in Brussels.

Agneessens later built up quite a career in Saint-Petersburg, but returned to Brussels in the 1880s. In the latter part of his life he suffered from a mental disorder. His works include Standing Male Nude (1870, sold 16 November 1994), Ladies by a Piano (sold 15 October 1998) and Bloemenstilleven (sold 7 December 2002).