Thomas Maxwell Harris FRS (8 January 1903 – 1 May 1983) was a British botanist.
He was educated at Bootham School, York,Wyggeston School, Leicester, University College, Nottingham and Christ's College, Cambridge.
He received his doctorate from the University of Cambridge and was a Fellow of the Royal Society. He served as President of the Linnean Society of London from 1961 to 1964.