John Turnbull Thomson (10 August 1821 – 16 October 1884) was a British civil engineer and artist who played an instrumental role in the development of the early infrastructure of nineteenth-century Singapore and New Zealand.
Thomson was born at Glororum, Northumberland, England, the third child of Alexander Thomson and his wife, Janet, née Turnbull.
After his father was killed in a hunting accident in 1830, the young Thomson and his mother went to live in Abbey St. Bathans, Berwickshire. He was educated at Wooler and Duns Academy, later spending some time attached to Marischal College, Aberdeen, and Edinburgh University before studying engineering at Peter Nicholson's School of Engineering at Newcastle-on-Tyne.
Thomson arrived in the Malay Straits in 1838 and was employed by the East India Survey. In 1841 he was appointed Government Surveyor at Singapore and in 1844 became Superintendent of Roads and Public Works.
He was responsible for the design and construction of a number of notable engineering works including bridges, roads, and hospitals. He conducted the allotment survey of Singapore, the topographical survey of the island of Singapore and its dependencies, and the marine survey of the Straits of Singapore and the east coasts of Johore and Penang. His outstanding achievement was the erection of the Horsburgh Lighthouse on Pedra Branca.