Ulefoss is a city located in Telemark county, Norway. It serves as the administrative centre of Nome Municipality and is situated along the northwest shore of Lake Norsjø.
The village occupies both sides of Ulefoss falls on the river Eidselva, positioned just before the water flows into the lake. Nearby settlements include Helgja to the southeast, Bjervamoen to the west, and Gvarv to the northwest.