The municipality is located in the small Ausseerland-Region within in the Styrian part of the Salzkammergut in the district of Liezen in Styria. Altaussee covers an area of 92.11 km ² and is located at 712 m above sea level on the western shore of Lake Altaussee on the southwestern edge of the Totes Gebirge. The community center is located in a valley, which is encircled by mountains. The most noticeable of these peaks are the Loser (1838 m) to the north, the Trisselwand (1755 m) to the east and the Sandling (1717 m) to the west. The highest mountain within the community area is the Schoenberg (2093 m) close to the border with Upper Austria. Due to the alpine location and the strong share of the Totes Gebirge about half of the municipal area consists of alpine wasteland, the rest are forests, grasslands and other land forms.