Robert Braithwaite Martineau (19 January 1826 – 13 February 1869)[1] was an English Victorian painter.

He studied under the Pre-Raphaelite artist William Holman Hunt and once shared a studio with him.

[1] His most famous painting, The Last Day in the Old Home, portrays the household of a feckless squire after gambling away his family's inheritance.

The man portrayed is Colonel John Leslie Toke (1839–1911) who was a friend of Martineau and was painted at his country home, Godinton House in Ashford, Kent.

Other paintings were bequeathed to the Ashmolean Museum in Oxford and Liverpool Art Gallery by his daughter Helen.