Olav Martinius Knutsen Steinnes (9 January 1886 – 26 June 1961) was a Norwegian educator and politician for the Labour Party and Nasjonal Samling.

After some years as a laborer he attended Møre Folk High School and then Volda Teachers' College from 1907 to 1910.

[1] During the German occupation of Norway he joined the Fascist party Nasjonal Samling.

In a letter to Kaare Fostervoll in the autumn of 1945, he said that his "series of inventions" would "bring honor and benefit to me and my country.

[2] On 1 February 1947, during the legal purge in Norway after World War II he was convicted of treason and sentenced to six months in prison and loss of his job.