Great Slave Lake (pronounced as SLAY-vi) is the second largest lake in the Northwest Territories of Canada, behind Great Bear Lake, and the deepest lake in North America at 614 meters (2,015 ft.). It is 480 kilometers long and 19 to 109 kilometers wide. It covers an area of 28,400 square kilometers in the southern part of the territory. Its volume is 2,090,000,000,000 cubic meters. The lake was named for the Slavey North American Indians.

British fur trader Samuel Hearne explored the area in 1771. In the 1930s, gold was discovered there, which lead to the establishment of Yellowknife, the territory's capital. Other towns around the lake include: Fort Providence , Hay River and Fort Resolution.

During winter Great Slave Lake is frozen enough for semitrucks to pass over. It is along a major trucking route to towns like Coppermine, Northwest Territories, Canada.

The Great Slave Lake is the deepest lake in North America, located on a continental tear, resulting in a rift lake .