布里恩茨湖（德语：Brienzersee）是瑞士伯尔尼州阿尔卑斯山北麓的一个湖泊，得名于东北侧的布里恩茨村。因特拉肯和Matten、Unterseen2个村庄位于西南侧。湖岸颇为陡峭，全湖几乎没有浅水区域。布里恩茨湖被称为瑞士最纯净的湖。

布里恩茨湖是阿勒河沿线的第一个湖泊，下游紧邻图恩湖。

布里恩茨湖东到布里恩茨村，西到因特拉肯，长14 km，阔 2.8 km，最深深度 261 m，面积 29.8 km²，湖面海拔高度 564 m。南岸有 Giessbach 瀑布和 Iseltwald岛。

2001年，布里恩茨湖的捕鱼量为10吨。1839年起开行客船，5条客船由当地铁路运营商BLS股份公司运营。

Lake Brienz (German:Brienzersee) is a lake just north of the Alps, in the Canton of Berne in Switzerland. It has a length of about 14 kilometres (8.7 mi), a width of 2.8 kilometres (1.7 mi) and a maximum depth of 260 metres (850 ft). Its area is 29.8 square kilometres (11.5 sq mi), and the surface is 564 metres (1,850 ft) above the sea-level. It is fed by the upper reaches of the Aar river at its eastern end and by the Lütschine river, flowing from the valleys of Grindelwald and Lauterbrunnen, at its south-western corner. It flows out into a further stretch of the Aar river at its western end. The culminating point of the lake's drainage basin is the Finsteraarhorn at 4,274 metres above sea level.