Thorstein Treholt (13 April 1911 – 17 March 1993) was a Norwegian politician for the Labour Party.
An agronomist by education, Treholt was state secretary to the Minister of Agriculture from 1954 to 1957, serving under three different ministers during the period (Rasmus Nordbø, Olav Meisdalshagen and Harald Johan Løbak).
Meanwhile, Treholt was appointed to cabinet his place was filled by Magne Kristian Mælumshagen and Åge Hovengen.
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.