Røyken is a district and village (bygd) and a former municipality in Buskerud in Viken County, Norway. In 2020 Røyken was merged with the municipalities of Hurum and Asker to form the new Asker Municipality (informally called "Greater Asker") located in the newly formed Viken county. The administrative centre of the municipality is the village of Midtbygda. The parish of Røken was established as a municipality on 1 January 1838 (see formannskapsdistrikt). Oslo ATCC, the Area Control Center for the controlled airspace above Østlandet is located here.