Тore Janson (born 1936) is a Swedish linguist and professor. Janson was professor of Latin at the University of Gothenburg, and later became professor of African languages at the same alma mater. He retired in 2001 but has since been affiliated with the University of Stockholm.
He devoted much of his time and publishing activities to the way how languages change as well as to the relationship between language and society.
He is the author of the international bestsellers Speak: A Short History of Languages and A Natural History of Latin.