Alf Martinius Grindrud (2 July 1904 – 17 May 1959) was a Norwegian politician for the Labour Party. During the German occupation of Norway he was a member of the Norwegian resistance movement. He was arrested in January 1944, and spent time at the concentration camps Grini, Natzweiler, Dachau, , and Vaihingen. In April 1945 sixteen Norwegians were liberated by the White Buses from Vaihingen, among them Grindrud and later Prime Minister Trygve Bratteli. Grindrud served as a deputy representative to the Norwegian Parliament from the Market towns of Buskerud county during the term 1945–1949.