Sandsvær is a area in Kongsberg, Buskerud county, Norway.
The area is identical to the former municipality named Sandsvær.
Sandsvær is situated in the valley of Lågendalen on the Numedalslågen river, and is bordered by Kongsberg town in the north, and the county border to Vestfold and Telemark counties in the south.
Historically, Sandsvær as a part of Sandsvær og Numedal fogderi had belonged to Akershus amt from 7 February 1685.
In 1760 Sandsvær fogderi was moved administratively to Buskerud.