Skaupsjøen is a lake in the municipalities of Eidfjord in Vestland county and Nore og Uvdal in Buskerud county, Norway. The 2.88 km2 lake lies just north of the Hardangervidda National Park on the vast Hardangervidda plateau. The lake outflows to the river Skaupa, which flows into the larger lake Halnefjorden to the northeast. The nearest road access is the Norwegian National Road 7, which passes about 5 km northwest of the lake.