Buechberg (also Buchberg) is an elongated molasse hill in the Swiss cantons of Schwyz and St. Gallen on Obersee lakeshore.

Situated on the southeastern Obersee lakeshore, the hill is situated on the area of the municipalities of Tuggen and Wangen−Nuolen in the canton of Schwyz, bordered by the lakeshore area in the canton of St. Gallen and by the Linth river towards Schmerikon.

Among the area around the Holzbrücke Rapperswil-Hurden lake crossing and between Rapperswil and Busskirch around Obersee, Güntliweid up to Bätzimatt at Buechberg are listed ast bird reserves of national importance.

[3] About two thousand years ago, Buechberg formed an island in the former flat Tuggenersee lake area, and there was probably at least one Roman watching tower on the hill established.

From Tuggen there's also a historical road heading from the former granary at the Grynau Castle over the Buechberg hill towards Siebnen.