Engelberg Abbey (German: Kloster Engelberg) is a Benedictine monastery in Engelberg, Canton of Obwalden , Switzerland. It was formerly in the Diocese of Constance, but is now in the Diocese of Chur. It is dedicated to Our Lady of the Angels and occupies a commanding position at the head of the Nidwalden Valley.

The Engelberg abbey was founded on the 1 April 1120 by Count Conrad of Sellenbüren, and its first abbot was Adelhelm, a monk of Muri Abbey . The first inhabitants of Engelberg were also monks from the Muri abbey. Von Sellenbüren entered the Engelberg abbey as a monk and died on the 2 Mai 1126.