Svein Gunnar Morgenlien (13 May 1922 – 22 September 2016) was a Norwegian trade unionist and politician for the Labour Party.
He was born in Aurskog as a son of smallholder and sawmill manager Johan Morgenlien (1878–1948) and housewife Ovidia Davidsen (1882–1970).
In the Norwegian Confederation of Trade Unions he was a member of the supervisory board from 1965 to 1977 and secretariat from 1979 to 1987.
He served as a deputy representative to the Parliament of Norway from the constituency Akershus during the terms 1961–1965, 1969–1973, 1973–1977 and 1977–1981.
In the entire fourth term he covered for cabinet members Inger Louise Valle and Helen Marie Bøsterud.