Rottach-Egern is located in the Tegernsee Valley, stretching southward from the shore of Lake Tegernsee to the Austrian border. The villages of Rottach, Egern, Gasse, Schorn, Sonnenmoos, Staudach, Weißach and Wolfsgrub have merged to become parts of a single settlement near the lake. More hamlets in the municipality are Berg, Ellmau, Hagrain, Haslau, Kalkofen, Oberach, Sutten and Trinis, Brandstatt, Enterrottach, Erlach, Kühzagl and Unterwallberg.
In Addition to the shoreline of the Tegernsee, The municipal area includes other small lakes of which Widrigsee (also Glocknersee), the Suttensee , the Riederecksee and Röthensteiner lakes are the main ones. The principal mountain range is part of the Mangfallgebirge, of which the Wallberg, at 1,722 metres (5,650 ft), with a cable car, is a venue for skiing, paragliding and the Wallenberg toboggan run.
The administrative center is in Rottach. The Catholic parish church of St. Lawrence is located in the district of Egern.