Black Jack is the nickname of the following people:
John Vernou Bouvier III (1891–1957), father of Jacqueline Kennedy Onassis
Jack Blackham (1854–1932), Australian cricketer
Jack Brabham (born 1926), Australian motor racing world champion
Jack Burdock (1852–1932), American Major League Baseball player and manager
Black Jack Christian (1856?–1897), American western outlaw
John Davidson (general) (1825–1881), American Civil War Union Army brigadier general and Indian fighter
Frederick Galleghan (1897–1971), Australian Army major general
Tom Ketchum (1863–1901), American western outlaw
John A. Logan (1826–1886), American Civil War general and politician
John McCauley (1899–1989), senior commander in the Royal Australian Air Force (RAAF)
Jack McDowell (born 1966), American Major League Baseball pitcher
John McEwen (1900–1980), 18th Prime Minister of Australia
John J. Pershing (1860–1948), United States Army general
Jean Schramme (1929–1988), Belgian mercenary and planter
Jack Stewart (ice hockey) (1917–1983), Canadian National Hockey League player
