Blue Mountain Lake is a reservoir in Arkansas, United States.

A U.S. Army Corps of Engineers Lake on the Petit Jean River in west central Arkansas, Blue Mountain Lake has approximately 50 miles of shoreline, located between Mount Magazine and the Ouachita Mountains just west of Havana, Arkansas.

Blue Mountain Dam was built in 1947 as a 115-foot-high, 2800-foot-long earthen structure, creating a reservoir with a surface area of about 4.5 square miles, about 50 miles of shoreline, and a maximum capacity of 258,000 acre-feet.

Dam and reservoir are owned by operated by the United States Army Corps of Engineers.

[1] The lake offers fishing, boating, swimming and camping; it is also the focal point of the view from the lodge atop Mount Magazine, home of Mount Magazine State Park.