The Socialist Left Party of Norway was founded in 1975. Its history shows a long-term rise in political influence, resulting in part from its emergence from older left-wing parties, especially the Socialist People's Party. After initial political setbacks in the 1970s, the party reorganized and regained support, particularly under Theo Koritzinsky (1983–87) and Erik Solheim (1987–97). Support dropped in the 1997 parliamentary election but rose again by the 21st Century, thanks to the party's position as the only sizeable party to the left of the Norwegian Labour Party. Labour's move further to the right under Jens Stoltenberg also helped the party's rise. By 2005, the Socialist Left Party had joined the Labour and Centre parties in Norway's governing Red-Green Coalition. The party has been led by Audun Lysbakken since 11 March 2012.

The Socialist Left Party is a democratic socialist political party in Norway. Positioned on the left-wing of the political spectrum, it is opposed to European Union and the European Economic Area membership. SV supports a strong public sector, stronger social welfare programs, environmentalism, and republicanism. As of 2018, the party had 11,385 members; the number has steadily increased since a low point in 2015. The party leader is Kirsti Bergstø, who was elected on 18 March 2023