Strömsund Municipality (Strömsunds kommun, Straejmien tjïelte) is a municipality in Jämtland County in northern Sweden. Its seat is located in Strömsund.
The nearest larger city is Östersund, the provincial capital of Jämtland, which is located approximately 100 km to the south.
Strömsund Municipality was formed in 1974 through the amalgamation of the former municipalities of Fjällsjö, Frostviken, Hammerdal and Ström. The most populous locality in the area, Strömsund, was chosen as administrative centre, and it also gave its name to the new entity.
With an area of roughly 12,000 km² (4,500 sq mi), it is the sixth largest in Sweden, and one of the most sparsely populated. The town Strömsund has a municipal population of about 3,500 and is located on the slopes of Ströms vattudal, the river that flows through the town. Among locals, the town itself is usually referred to as Ström or Flata (a reference to the flack slope on which the centra