Jølstravatnet or Jølstravatn is a lake in the municipality of Jølster in Sogn og Fjordane county, Norway. The lake empties its water into the long Jølstra river which then flows into the Førdefjorden. The impressive eastern arm of Jølstravatn is called Kjøsnesfjorden, although it is not a true fjord that is part of the sea. The villages of Skei, Helgheim, Ålhus, and Vassenden are located on the shores of the lake.