Oskar Mendelsohn (29 March 1912 – 1 August 1993) was a Norwegian educator, non-fiction writer and historian. He was born in Trondheim. Among his books is a two-volume work on the history of Jews in Norway, published in 1969 and 1986. In 1990 he published a book on the persecution of Jews in Norway during World War II (English edition in 1991). He was decorated Knight, First Class of the Order of St. Olav in 1989.