Robert Colquhoun (1914 – 1962) was a Scottish painter, printmaker and theatre set designer.
Born in Kilmarnock, Colquhoun won a scholarship to study at the Glasgow School of Art, where he met Robert MacBryde with whom he established a lifelong romantic and professional relationship, the pair becoming known as "the two Roberts".
He joined MacBryde on a travelling scholarship to France and Italy from 1937 to 1939, before serving as an ambulance driver in the Royal Army Medical Corps during the Second World War. After being injured, he returned to London in 1941 where the pair shared studio space whilst living with John Minton.
Colquhoun's early works of agricultural labourers and workmen were strongly influenced by the colours and light of rural Ayrshire. His work developed into a more austere, Expressionist style, heavily influenced by Picasso, and concentrated on the theme of the isolated, agonised figure. From the mid-1940s to the early 1950s he was considered one of the leading artists of his generation. Along with that of MacBryde, the work of Colquhoun was regularly shown at the Lefevre Gallery in London.
At the height of their acclaim they courted a large circle of friends - including Michael Ayrton, Francis Bacon, Lucian Freud and Dylan Thomas - and were renowned for their studio parties. Colquhoun was also a prolific printmaker, producing a large number of lithographs and monotypes throughout his career.
Robert Colquhoun died in London in 1962.