Murphy is an unincorporated community in Owyhee County, Idaho, United States. The county seat of Owyhee County, it is one of the smallest county seats nationwide. Murphy formed around a railhead of the Boise, Nampa and Owyhee Railroad built in 1899. The town succeeded Silver City as county seat in 1934. The railroad operated until 1947. The community is named after Cornelius "Con" Murphy, a Boise, Nampa and Owyhee Railroad crew boss. Murphy is located 25 miles south of Nampa. Murphy is part of the Boise City–Nampa, Idaho Metropolitan Statistical Area.