Simensen is a surname. Notable people with the surname include:
Bjørn Simensen (1947–2025), Norwegian culture administrator and journalist Don Simensen (1926–1994), American football player Jarle Simensen (born 1937), Norwegian historian Kåre Simensen (born 1955), Norwegian politician for the Labour Party Karen Simensen (married name Klæboe) (1907–1996), Norwegian figure skater Sigurd Simensen (1888–1969), Norwegian newspaper editor and politician
See also Simensen Peak, standing on the north side of Glitrefonna Glacier in the Sor Rondane Mountains of Antarctica Simonsen