John Flannagan may refer to:
John Flannagan (Medal of Honor) (born 1852), American sailor and Medal of Honor recipient John Flannagan (priest) (1860–1926), Catholic priest and president of St. Ambrose College John Bernard Flannagan (1895–1942) American sculptor John W. Flannagan, Jr. (1885–1955), American politician
See also John Flanagan (disambiguation)