McKellar is a surname. Notable people with the surname include:
Archibald McKellar (1816–1894), Canadian politician
Archie McKellar (1912–1940), Royal Air Force fighter pilot during the Battle of Britain in World War II.
Colin McKellar (1903–1970), Australian farmer, soldier and federal politician
Crystal McKellar (born 1976), American actress and younger sister to Danica
Danica McKellar (born 1975), American actress and older sister to Crystal
Daniel McKellar (1892–1917), Scottish footballer
Don McKellar (born 1963), Canadian actor, writer, and filmmaker
John McKellar (1833–1900), Canadian businessman and politician
John McKellar (writer) (1930–2010), Australian playwright, social satirist
Kenneth McKellar (politician) (1869–1957), American politician
Kenneth McKellar (singer) (born 1927), Scottish singer
Earl McKellar (1918–1976), Canadian politician
Phil McKellar, Australian record producer
