George Aitchison Jr. RA (London 7 November 1825 – 16 May 1910) was a British architect. He was the son of George Aitchison (1792–1861) who was educated at Merchant Taylors' School and University College London and articled to architect Henry Hake Seward from 1813 to 1823. His best-known work is Leighton House, Kensington, for Baron Leighton.