Gusinoye Lake, Freshwater lake in Buryatia, Russia.

Gusinoye Lake is a freshwater lake in the Russian republic of Buryatia, set between two mountain ridges at an elevation of around 550 meters (1,800 feet). It is one of the larger lakes in the region, with low hills running close to its shores on most sides.

In the late 17th century, Semyon Remezov's map showed three crescent-shaped ponds on the site. Around 1730 flooding began, and by the 1740s tectonic subsidence and the 1742 earthquake formed a single lake, prompting Buryat uluses to move toward the Khamar-Daban ridge. The Tsagan-Gol channel broke through in 1749, and the Bayan-Gol outflow to the Selenga appeared in 1783.

The Tamchinsky Datsan monastery stands on the western shore and is one of the oldest Buddhist monasteries in Russia. Pilgrims visit it regularly, and the lake is considered a sacred place within that tradition.

The town of Gusinoozyorsk on the northeastern shore has lodging and basic services for visitors. From there the waterfront is easy to reach on foot, and the surrounding area is suited for walking and fishing.

The Buryat name Khülen nuur means "leg-lake", recalling the 18th century when several small lakes in the basin could be waded across. The Russian name comes from the geese that once gathered on Oseryodysh Island, which has since sunk; the birds are no longer numerous either.