•
Barry O'Halloran, Irish journalist •
Brian O'Halloran, American actor •
David O'Halloran, Australian Rules footballer •
Dustin O'Halloran, American pianist and composer •
Greg O'Halloran, Irish footballer •
Hal O'Halloran, American radio announcer and singer •
Jack O'Halloran, American boxer and actor •
James O'Halloran (politician), Canadian lawyer and politician •
Joseph O'Halloran, (1763–1843), major-general in the East India Company •
Kay O'Halloran, Australian-born academic •
Keith O'Halloran, Irish footballer •
Kevin O'Halloran (1937–1976), Australian swimmer •
Kevin O'Halloran (footballer) (1915–1976), Australian Rules footballer •
Mark O'Halloran (rugby league), Australian Rugby League player •
Mark O'Halloran (writer), Irish actor and screenwriter •
Martin O'Halloran (fl. 1879–1881), member County Galway Land League •
Michael O'Halloran (disambiguation), several people, including :*
Michael O'Halloran (UK politician), English politician :*
Michael O'Halloran (footballer), Scottish footballer •
Mick O'Halloran (1893–1960), South Australian politician •
Sharyn O'Halloran, Professor of Political Economics at Columbia University •
Stephen O'Halloran (born 1987), (soccer) footballer with Stalybridge Celtic •
Sylvester O'Halloran (1728–1807), Irish doctor •
Thomas O'Halloran (disambiguation), several people, including: •
Thomas O'Halloran (Australian footballer) (1904–1956), Australian rules (VFL) footballer playing for Richmond •
Thomas Shuldham O'Halloran (1797–1870), South Australian police commissioner •
Thomas Joseph Shuldham O'Halloran (1835–1922), his son, magistrate and minor football identity •
Thomas Shuldham O'Halloran (lawyer) (1865–1945), his grandson, SAFL football official •
Tom O'Halloran (Australian footballer) (1892–1970), Australian rules (VFL) footballer with South Melbourne •
Tom O'Halloran (climber) (born 1992), Australian professional rock climber •
William O'Halloran (trade unionist) (born 1870), trade union pioneer in Galway, Ireland •
William O'Halloran (cricketer) (1934–1994), Australian cricketer •
William Littlejohn O'Halloran (1806–1885), British Army officer and public servant in South Australia ==Places==