McDonald Peak, Mountain summit in Mission Range, Montana, US

McDonald Peak is the highest summit in the Mission Range of northwestern Montana, reaching 9,820 feet (2,993 m). It lies in Lake County within the Flathead Indian Reservation, southeast of Flathead Lake, and its north slope holds McDonald Glacier, the largest glacier in the range.

McDonald Peak is the highest summit of the Mission Range, a range in northwestern Montana. The McDonald Glacier on its north slope was about 1 kilometre long in 1966; by 2005 it had shrunk by 45 percent, the largest glacier in the range.

McDonald Peak lies within the Flathead Indian Reservation in Lake County, Montana. The reservation is home to the Confederated Salish and Kootenai Tribes, and the peak stands on tribal land, so access is governed by the tribes rather than by state or federal agencies. The summer closure protecting grizzly bears is a conservation measure applied on this land.

The summit and surrounding area are closed to hikers from July 15 to September 30, when grizzly bears feed on insects there. Plan any climb outside that window; the peak lies within the Flathead Indian Reservation in Lake County, northwestern Montana, southeast of Flathead Lake.

McDonald Peak's topographic prominence of 9,820 feet is the second greatest of any summit in Montana, after Crazy Peak; the next highest mountain in the state lies almost 80 miles (130 km) away. Its north slope holds McDonald Glacier, the largest in the Mission Range, which measured 1 km long in 1966 and had shrunk by 45% by 2005.