John Walker is an English painter and printmaker. He has been called "one of the standout abstract painters of the last 50 years."

Walker studied in Birmingham at the Moseley School of Art, and later the Birmingham School of Art and Académie de la Grande Chaumière in Paris. Some of his early work was inspired by abstract expressionism and post-painterly abstraction, and often combined apparently three-dimensional shapes with "flatter" elements. These pieces are usually rendered in acrylic paint.

In the early 1970s, Walker made a series of large Blackboard Pieces using chalk first exhibited at the opening of Ikon Gallery, in Birmingham Shopping Centre, Birmingham in 1972 and the Juggernaut works which also use dry pigment. From the late 1970s, his work marked allusions to earlier painters, such as Francisco Goya, Édouard Manet and Henri Matisse, either through the quoting of a pictorial motif, or the use of a particular technique. Also during this time, he began to use oil paint more in his work. His paintings of the 1970s are also notable for what has come to be termed canvas collage – the application of glued-on, separately painted patches of canvas to the main canvas (see the external link below for an example and image).

After spending some time in Australia, Walker got a position at the Victoria College of the Arts in Melbourne. He produced the Oceania series around this time which incorporates elements of native Oceanic art.

Walker is currently the head of the graduate painting program at Boston University.

Walker won the 1976 John Moores Painting Prize and was nominated for the Turner Prize in 1985.

In September 2010, Walker and five other British artists including Howard Hodgkin, John Hoyland, Ian Stephenson, Patrick Caulfield and R.B. Kitaj were included in an exhibition entitled The Independent Eye: Contemporary British Art From the Collection of Samuel and Gabrielle Lurie, at the Yale Center for British Art.