Carstairs is a surname. Notable people with the surname include:
Henrietta Carstairs (1777/78 – after 1817), British mountaineer and nanny Carroll Carstairs (1888–1948), American art dealer George Carstairs (rugby league) (1900–1966), Australian rugby league player Joe Carstairs (1900–1993), British power boat racer John Paddy Carstairs (1910–1970), British film and television director Steven Carstairs (1910–1998), Scottish radiologist Morris Carstairs (1916–1991), British psychiatrist and anthropologist Alan Carstairs (born 1939), Australian politician Sharon Carstairs (born 1942), Canadian politician Jim Carstairs (born 1971), Scottish footballer
Fictional characters: Lt. Fairfax and Lt. Carstairs, from the BBC sitcom 'Allo 'Allo! James "Jem" Carstairs, from The Infernal Devices series by Cassandra Clare
See also William Carstares (1649–1715), minister of the Church of Scotland