Henry O'Neill (disambiguation)

Henry O'Neill (1891–1961) was an American film actor.

Henry O'Neill may also refer to:
 * Henry O'Neill (d. 1347), king of Tyrone
 * Henry O'Neill (illustrator) (1798–1880), Irish artist and antiquarian
 * Henry O'Neill (darts player), Northern Irish darts player
 * Henry O'Neill, 2nd Baron Dungannon, held title Baron Dungannon
 * Sir Henry O'Neill, 3rd Baronet (c. 1674–1759) of the O'Neill baronets
 * Sir Henry O'Neill, 1st Baronet (1625-c. 1680) of the O'Neill baronets
 * Henry E. O'Neill (1848–1925), British explorer of Central Africa
 * Henry MacShane O'Neill (died 1622), leader of the MacShane (not to be confused with MacShane's of Loughinsholin)
 * Sir Henry Og MacShane, son of Henry MacShane O'Neill; see
 * Henry O'Neill (bishop) (1843–1915), Irish bishop of Dromore