McGrain is a surname. Notable people with the surname include:
Danny McGrain (born 1950), Scottish international footballer Danny McGrain (footballer, born 1953) (1953–2004), Scottish footballer Myrtle McGrain (1883–1980), American actress Tommy McGrain (born 1959), Scottish footballer
See also McGrain v. Daugherty, a United States Supreme Court case Kintner-McGrain House, a historic building in Corydon, Indiana