Austdalsvatnet is a lake in the northwestern part of the municipality of Luster in Sogn og Fjordane county, Norway. It is located in the Breheimen mountain range at the end of the Austdalsbreen glacier, just north of the lake Styggevatnet. It is about 10 kilometres (6.2 mi) east of Lodalskåpa and Brenibba, in the Jostedalsbreen glacier.