Seimsdalen is a valley in Årdal Municipality in Vestland county, Norway.

The valley is located 3 kilometres (1.9 mi) west of the municipal center of Årdalstangen, to which it is connected via a 1.5 kilometres (0.93 mi) long Seimsdalstunnelen [no].

The village of Indre Offerdal lies about 10 kilometres (6.2 mi) to the southwest.

The population of the valley is 467 (2013).

This Vestland location article is a stub.