Roland John Thornhill (born September 3, 1935) is a Canadian politician. He represented the electoral district of Dartmouth South in the Nova Scotia House of Assembly from 1974 to 1993. He is a member of the Progressive Conservative. Thornhill was born in Grand Bank, Newfoundland and Labrador. He attended the Memorial University of Newfoundland and Dalhousie University and was a stockbroker. From 1967 to 1973, he served as mayor of Dartmouth, Nova Scotia. In 1955, he married Joyce Marie Moore. Thornhill is currently a financial consultant at Clarke, Inc.