Flagg is a surname. Notable people with the surname include:
Abner S. Flagg (1851-1923), American politician
Azariah C. Flagg, American politician
Ernest Flagg (1857–1947), American architect
Fannie Flagg (born 1944), American author
George Whiting Flagg (1816–1897), American painter
James Montgomery Flagg (1877–1960), American artist
Jared Bradley Flagg (died 1899), American artist
Russell de Gree Flagg (1892–1980), American luthier
Wilson Flagg (1938–2001), American admiral
Ella Flagg Young (1845–1918), American educator
Ray Dennis Steckler or Cash Flagg (1938–2009), American film director
Fictional characters:
General Flagg, two characters in the G.I. Joe universe
Harry Flagg, a character in the British soap opera Coronation Street
Randall Flagg, a villain in several Stephen King novels
Sam Flagg, a character in the TV series M*A*S*H
Brick Flagg, a character in the animated series Kim Possible
