Lessore comes from a family of artists: his uncle was Walter Sickert, and his mother Helen Lessore was both a painter and director of the Beaux Arts Gallery in London.

He worked as a figurative artist, although rarely painting from life. Instead he worked from sketches and memories, often building up a composition over a long period of time. He was born in London and studied at the city’s Slade School of Fine Art, from 1957-61. On leaving he won a travelling scholarship to Italy. In 1965 he began teaching at the Royal Academy Schools, a post he held until 1999.

Leon Kossoff painted John Lessore regularly, beginning in the 1950s and a portrait of the same sitter, entitled Man in a Wheelchair, 1959-1962, is also in the collection of the Tate, London.