Satyrium edwardsii, the Edwards' hairstreak, is a species of butterfly in the family Lycaenidae. It is found in the eastern parts of the United States and in the southern parts of the Canadian provinces from Saskatchewan to Quebec. Larvae feed on Quercus species, including Q. ilicifolia The Edward's hairstreak is an endangered species, and one of the places to find them is at Adams Lake, Ohio, in the prairie area.