James Allan Thomson (27 July 1881 – 6 May 1928) was a New Zealand geologist, scientific administrator and museum director. He was born in Dunedin, New Zealand, in 1881, where his father was a science teacher at Otago Boys' High School. He graduated from the University of Otago in 1904, the same year as Sir Peter Buck. Selected as New Zealand's first Rhodes Scholar, Thomson studied geology, played rugby, rowed and ran at St John's College, Oxford. His daughter Margaret became a noted film director.