Olaf Broch (4 August 1867, Horten – 28 January 1961, Oslo) was a Norwegian linguist. He was born in Horten, and was a brother of children's writer Lagertha Broch, zoologist Hjalmar Broch, and social worker Nanna Broch. He was a professor of Slavic languages at the University of Oslo from 1900 to 1937. Among his works are Slawische Phonetik from 1911, Håndbok i elementær fonetikk from 1921, and Proletariatets diktatur from 1923. He translated works by Leo Tolstoy and Fyodor Dostoyevsky into Norwegian. He was decorated Commander of the Order of St. Olav in 1946.