The Bambuyka (Russian: Бамбуйка) is a river in Buryatia, southern East Siberia, Russia. It is 172 kilometres (107 mi) long, and has a drainage basin of 4,170 square kilometres (1,610 sq mi).

The only inhabited place in the area is Bambuyka, Muysky District, a small hamlet located close to the mouth of the river.

The Bambuyka is a left tributary of the Vitim. Its sources are in a small lake close to the southwestern slope of Muisky Gigant, the highest peak of the Southern Muya Range. The river flows first in a SSE direction across mountainous terrain. It bends east close to the east of a sharp bend of the Tsipa and flows roughly in an eastward direction. Then it bends again and flows southeastwards. In its lower course it bends gradually, meandering northeastwards in a floodplain, until it finally meets the left bank of the Vitim 812 kilometres (505 mi) from its mouth in the Lena.

The longest tributaries of the Bambuyka are the 75 kilometres (47 mi) long Bambukoy on the left, as well as the 42 kilometres (26 mi) long Pashkov-Klyuch and the 55 kilometres (34 mi) long Golyube on the right.

• List of rivers of Russia

• Media related to Bambuyka at Wikimedia Commons