Little Redfish Lake, Glacial lake in Sawtooth Mountains, Idaho, US.

Little Redfish Lake is a mountain lake on Redfish Lake Creek in Custer County, Idaho, about 1 mile downstream from the larger Redfish Lake. It lies at 6,489 feet on the northeast edge of the Sawtooth Range within the Sawtooth National Recreation Area, 5 miles south of Stanley along State Highway 75, and drains to the Salmon River.

The lake was carved by glaciers during the ice age as part of the Sawtooth Mountains' geological story. The area gained cultural attention in the 1960s when writers visited and drew inspiration from the mountain landscape and its fishing grounds.

Both Redfish lakes take their name from the red-scaled sockeye salmon that returned each year to spawn via the Salmon River before dams were built on the lower Snake River. The species is the sockeye, not a generic red fish, and the run has not survived the dams.

The lake is accessible year-round for fishing, with brook trout and bull trout available under local regulations. Access comes via established mountain trails from nearby settlements, and visitors should prepare for high-altitude conditions.

Richard Brautigan wrote parts of his 1961 novella Trout Fishing in America while camping near Little Redfish Lake, and the lake appears in several chapters of the book.