The Rock Ptarmigan nests on bare, often stony mountain ground. The nest is a simple scrape that the female makes and lines sparingly. She usually lays 5–9 eggs, which she incubates alone for about three weeks. The young are nidifugous, leaving the nest shortly after hatching and finding food themselves under the female's watch. The well-camouflaged plumage protects both the incubating female and the chicks.