Blådalsvatnet is a glacial lake in the municipality of Kvinnherad in Hordaland county, Norway. The 2.89-square-kilometre (1.12 sq mi) lake lies just outside the Folgefonna National Park, about 10 kilometres (6.2 mi) north of the village of Indre Matre. The lake is formed by the glacial runoff from the large Folgefonna glacier located just north of the lake.