Brian O'Neill may refer to:
Arts and entertainment Brian D. O'Neill (born 1949), American author and attorney Brian O'Neill (journalist) (c. 1900–1975), English and Irish journalist and author Brian O'Neill, fictional Irish gangster in Mafia II
Sports Brian O'Neill (ice hockey, born 1929) (1929–2023), Canadian executive in the National Hockey League Brian O'Neill (ice hockey, born 1988), American ice hockey player Brian O'Neill (American football) (born 1995), American football offensive tackle
Others Brian McPhelim O'Neill (died 1574), lord of Lower Clandeboye Brian MacArt O'Neill (died 1607), member of the O'Neill Dynasty Brian J. O'Neill (born 1949), American politician Brian O'Neill (superintendent) (1941–2009), American superintendent of the Golden Gate National Recreation Area Brian O'Neill (High-King of Ireland) (died 1260) Brian C. O'Neill (born 1965), American earth system scientist and demographer Brian O'Neill, Baron Dungannon (died 1562), Irish aristocrat Sir Brian O'Neill, 2nd Baronet (died 1694), Irish landowner, barrister and judge Brian O'Neill (died 1617), Irish noble Brian O'Neill (d. 1295) (c. 1265–1295), king of Tyrone Brian Ballagh O'Neill(died 1425), Irish noble Brian Ballagh II O'Neill (died 1529), Irish noble
See also Brian O'Neil (disambiguation)