John Middleton was an English artist known for his accomplished watercolour paintings. He was the youngest and the last important member of the Norwich School of painters, which was the first provincial art movement in Britain. As well as being a talented etcher, he produced oil paintings and was an enthusiastic amateur photographer.

Middleton's father, also named John, was a Norwich glass stainer. His mother painted plants and twice exhibited her work with the Norwich Society of Artists. Middleton was educated in Norwich and studied art under the landscape painters John Berney Ladbrooke and Henry Bright. He first exhibited his paintings before the age of twenty and went on to show paintings at both the Royal Academy and the British Institution. Many of his works have been acclaimed by art historians for their masterly tonal values, confidence and freshness, which gives them a more modern appearance in comparison with the sometimes over-detailed works of other Victorian painters.

His death in 1856 from tuberculosis, which cut short his career at the age of 29, has been described by the art historian Josephine Walpole as "the supreme tragedy for the Norwich School of painters".