Francis Sylvester Walker was an Irish painter, illustrator and etcher.

Walker was the son of Thomas Walker, Master of the Workhouse at Dunshaughlin, and Ann Delany of Clavistown Mills, Killmessan, County Meath. He studied Art at both the Royal Dublin Society (RDS) and the Royal Hibernian Academy (RHA) in Dublin. He exhibited at the RHA in 1863, at Burlington House, London in 1905, and in various cities in Britain (Birmingham, Liverpool, Glasgow etc.). He also became a member of the Royal Society of Painter-Etchers and Engravers (RE).

Walker painted landscapes, portraits and genre works and provided illustrations for various travel books. His works are currently exhibited in places such as the National Gallery of Ireland in Dublin, the British Museum and Victoria and Albert Museum in London.