Thorstein Treholt (13 April 1911 – 17 March 1993) was a Norwegian politician for the Labour Party. He was the father of convicted Norwegian spy Arne Treholt.
As an elected politician he was elected to the Norwegian Parliament from Oppland in 1958, and later re-elected on four occasions. On the local level he was a member of the municipality councils of Nord-Aurdal 1951–1955, Brandbu 1959–1961 and Gran from 1962 to 1967.
His career in politics ended with the post of County Governor of Oppland, which he held from 1976 to 1981.