Professor Robert Ture Olov Janse (August 3, 1892, in Norrköping, Sweden – March 1985, in Washington, D.C., United States) was a Swedish archaeologist. He is notable for his excavation work at Đông Sơn between 1935 and 1939. Though he originally argued a viewpoint for the European origins of Bronze Age culture in Vietnam, he reversed himself in support of Chinese origins after he started excavations at Đông Sơn. Janse is characterized as having introduced order into the research of the history of archaeology in Mainland Southeast Asia.