John Hartigan may refer to:
People John A. Hartigan (born 1937), Australian-American statistician John Patrick Hartigan (1887–1968), American jurist John Hartigan, American captain of 1911 Boston College football team John Hartigan (rowing) (1940–2020), American coxswain John Hartigan (media executive) (born 1947), Australian journalist John C. Hartigan, American Emmy nominee in 2014 Primetime Emmy Award for Outstanding Special Visual Effects John Hartigan, Australian director of Land Registry, subordinate in 2001 to Elizabeth O'Keeffe John Hartigan, English Labour Party candidate in Shipston ward of 2017 Warwickshire County Council election
Characters John Hartigan (Sin City), major protagonist in 1990s American graphic novels by Frank Miller