Winisk Lake (French: lac Winisk) is a large, irregularly-shaped lake in the Unorganized Part of Kenora District in northwestern Ontario, Canada.

It is on the Winisk River, and is part of the Hudson Bay drainage basin.

The lake is about 35 kilometres (22 mi) long and 19 kilometres (12 mi) wide and lies at an elevation of 193 metres (633 ft).

The primary outflow is the Winisk River at the north, which flows to Hudson Bay.

This Northern Ontario geographical article is a stub.