Splügen (Romansh: Spleia, Italian: Spluga) is a former municipality in the Viamala Region in the Swiss canton of Graubünden. On 1 January 2006 Splügen incorporated its neighbouring municipality of Medels im Rheinwald. On 1 January 2019 the former municipalities of Hinterrhein, Nufenen and Splügen merged to form the new municipality of Rheinwald.
In 1995, the Swiss Heritage Society bestowed the Wakker Prize to Splügen.