|Location||Cheshire County, New Hampshire|
|Primary outflows||Contoocook River|
|Basin countries||United States|
|Max. length||2.8 mi (5 km)|
|Max. width||0.5 mi (1 km)|
|Surface area||344 acres (1.4 km2)|
|Average depth||7 ft (2.1 m)|
|Max. depth||23 ft (7.0 m)|
|Surface elevation||1,007 feet (307 m)|
Contoocook Lake (/ /(listen)) is a 344-acre (1.4 km2) water body located in Cheshire County in southwestern New Hampshire, United States, in the towns of Jaffrey and Rindge. The lake, along with Pool Pond, forms the headwaters of the Contoocook River, which flows north to the Merrimack River in Penacook, New Hampshire.
The lake is classified as a warmwater fishery, with observed species including largemouth bass, smallmouth bass, white perch, yellow perch, black crappie, bluegill, pumpkinseed, chain pickerel, and horned pout.