Donaldson Peak, Mountain summit in Lost River Range, Idaho, United States

Donaldson Peak is a 12,023-foot (3,665 m) summit in the Lost River Range, within Salmon-Challis National Forest in Custer County, Idaho. It stands 0.65 miles (1.05 km) east of Mount Church, its line parent, and 1.4 miles (2.3 km) west of Mount Breitenbach. The peak is the eighth-highest in Idaho and the seventh-highest in the range.

Donaldson Peak is named for Charles R. Donaldson, who lived from 1919 to 1987 and served as Chief Justice of the Idaho Supreme Court. The name honors the jurist rather than marking any event on the mountain itself. The peak stands in Salmon-Challis National Forest in Custer County, 0.65 miles east of Mount Church, its line parent.

The mountain forms part of the Idaho 12ers, a group of nine peaks above 12,000 feet that attract mountaineers from across the country.

The mountain can be reached through two main routes: Jones Creek or North Fork Jones Creek, with the latter offering more stable ground conditions. Both paths require good endurance and scrambling experience.

Donaldson Peak is the eighth-highest summit in Idaho and the seventh-highest in the Lost River Range, standing 0.65 miles (1.05 km) east of Mount Church, its line parent, and 1.4 miles (2.3 km) west of Mount Breitenbach. It lies in Salmon-Challis National Forest, Custer County.