George Robert Lewis was a versatile English painter of landscapes and portraits.

The younger brother of Frederick Christian Lewis and of Charles Lewis the bookbinder, he was born in London on 27 March 1782. He studied under Henry Fuseli in the schools of the Royal Academy, and worked on both nature and antiquities.

Lewis sent landscapes to the exhibitions of 1805–7; he at that time lived with his brother Frederick at Enfield, and worked for him on John Chamberlaine's Original Designs of the most celebrated Masters and William Young Ottley's Italian School of Design, for both of which he made aquatint plates. In 1813, he toured North Wales with John Linnell. In 1818, he accompanied Thomas Frognall Dibdin, to make drawings, on a continental journey, and his illustrations to the Bibliographical and Picturesque Tour through France and Germany were published in 1821.

From 1820 to 1859, Lewis exhibited portraits, landscapes, and figure subjects at the Royal Academy, the British Institution, the Suffolk Street Gallery, and the Oil and Water-colour Society. He died at Hampstead on 15 May 1871.