Botnsvatnet or Botsvatnet is a lake in the municipality of Valle in Agder county, Norway. The 5.61-square-kilometre (2.17 sq mi) lake is located just north of the lakes Rosskreppfjorden and Kolsvatnet and the mountain Urddalsknuten, and it lies to the southeast of the mountain Bergeheii. The village of Valle is located about 14 kilometres (8.7 mi) to the east of the lake. The lake sits at an elevation of 1,020 metres (3,350 ft) above sea level.

• List of lakes in Aust-Agder
• List of lakes in Norway