List of people with surname O'Brien

O'Brien is a surname of Irish origin. It has many variants in the Irish diaspora worldwide, such as Brien, O'Bryan, O'Brian, Brian, O'Brine and O'Bryen which all claim a general common ancestry. The original Gaelic surname is Ó Briain (plural, Uí Briain). Notable people with the name include:

A

 * Aidan O'Brien (b. 1969), Irish race horse trainer
 * Aiden O'Brien, Irish football player
 * Alan O'Brien, Irish association football player
 * Alex O'Brien (b. 1970), professional American tennis player
 * Ambrose O'Brien
 * Andy O'Brien (disambiguation), various
 * Anne O'Brien (disambiguation), various
 * Arthur O'Brien
 * Austin O'Brien

B

 * Barry O'Brien
 * Billy O'Brien (baseball) (1860–1911), American baseball player
 * Billy O'Brien (footballer), Welsh association football player
 * Brendan O'Brien (disambiguation), various
 * Brenna O'Brien
 * Brock O'Brien
 * Buck O'Brien
 * Burton O'Brien

C

 * Cathy O'Brien (athlete) (b. 1967), American long-distance runner
 * Cathy O'Brien (conspiracy theorist) (b. 1957), purported American child-slave/sex-abuse victim
 * Charles O'Brien (disambiguation), various
 * Christian O'Brien (1914-2001), British geologist, author & historian
 * Ciaran O'Brien
 * Cinders O'Brien
 * Clinton O'Brien (b. 1974), Australian rugby league footballer
 * Conal O'Brien
 * Conan O'Brien (b. 1963), US comedian and talk show host
 * Connor O'Brien (disambiguation)
 * Conor O'Brien (disambiguation), various
 * Cubby O'Brien

D

 * Daniel O'Brien (disambiguation), various
 * Danielle O'Brien
 * Danny O'Brien (disambiguation), various
 * Dara Ó Briain, Irish comedian and presenter
 * Darcy O'Brien (1939–1998), American true crime author
 * Daryl O'Brien (b. 1941), Australian footballer (Australian rules football)
 * Dave O'Brien (actor) (1912–1969), American film actor
 * Dave O'Brien (sportscaster), American sportscaster
 * David O'Brien (disambiguation), various
 * Doug Brien (born 1970), former American football placekicker
 * Don Brien (born 1959), Canadian sprint canoer, who competed in the mid to late 1980s
 * Declan O'Brien, president of Utopia Pictures & Television, and a writer and producer
 * Declan O'Brien (footballer)
 * Dennis O'Brien (disambiguation), various
 * Derek O'Brien (disambiguation), various
 * Dermod O'Brien (1865–1906), Irish painter
 * Donald O'Brien (disambiguation), various
 * Doug O'Brien
 * Dylan O'Brien (b. 1991), American actor

E

 * Ed O'Brien (b. 1968), English musician
 * Edmond O'Brien (1915–1985), American actor
 * Edna O'Brien (b. 1930), Irish novelist
 * Edward O'Brien (disambiguation), various
 * Edwin Frederick O'Brien, Grand Master of the Equestrian Order of the Holy Sepulchre of Jerusalem
 * Eileen O'Brien (disambiguation), various
 * Elaine O'Brien, American politician
 * Erin O'Brien (writer), American writer
 * Erin Joanne O'Brien (1934–2021), American actress
 * Eugene O'Brien (disambiguation), various

F

 * Fergal O'Brien, Irish professional snooker player
 * Fergus O'Brien (1930–2016), Irish politician
 * Fitz James O'Brien, Irish born American novelist
 * Flann O'Brien, pen name of Irish novelist and satirist Brian O'Nolan

G

 * Gareth O'Brien
 * Geraldine O'Brien
 * George O'Brien (disambiguation), various
 * Ger O'Brien
 * Geoffrey O'Brien
 * Glenn O'Brien
 * Gray O'Brien
 * Gavin O'Brien

H

 * Harry O'Brien (changed his name in 2013 to "Heritier Lumumba")
 * Harry J. O'Brien
 * Helen O'Brien (1925–2005), British nightclub owner and spy
 * Henry O'Brien (disambiguation), various
 * Hod O'Brien (1936–2016), American jazz pianist
 * Hugh O'Brien (1827–1895) mayor of Boston

I

 * Iain O'Brien
 * Ian O'Brien
 * Ignatius O'Brien, 1st Baron Shandon (1857–1930), Lord Chancellor of Ireland, 1913–1918

J

 * Jack O'Brien (disambiguation), various
 * Jake O'Brien (fighter), MMA fighter
 * Jake O'Brien (footballer), Irish footballer
 * James O'Brien (disambiguation)
 * Jamie O'Brien (disambiguation), various
 * Jeremiah O'Brien (1744–1818), US Navy officer of the American Revolutionary War
 * Jesse O'Brien (disambiguation), various
 * Jim O'Brien (disambiguation)
 * Joan O'Brien
 * Joe O'Brien (disambiguation), various
 * Joey O'Brien
 * John O'Brien (disambiguation), various
 * Joseph O'Brien (disambiguation), various

K

 * Kate O'Brien (disambiguation)
 * Katharine O'Brien
 * Katherine O'Brien
 * Kathleen O'Brien
 * Katie O'Brien, British female tennis player
 * Keith O'Brien (1938-2018), Roman Catholic Cardinal Archbishop of Saint Andrews and Edinburgh
 * Ken O'Brien
 * Kerry O'Brien (disambiguation)
 * Kevin O'Brien (disambiguation), various
 * Kieran O'Brien
 * Kim O'Brien, American film and television actress
 * Kirsten O'Brien (born 1972), British TV presenter
 * Kitt O'Brien (born 1990), American football player
 * Kitty Wilmer O'Brien, Irish painter

L

 * Larry O'Brien (1917–1990), American politician
 * Larry O'Brien (Canadian politician), Canadian entrepreneur and politician; Mayor of Ottawa, 2006–2010
 * Laurence O'Brien
 * Lawrence D. O'Brien
 * Leighton O'Brien
 * Lévis Brien (born 1955), Quebec politician
 * Leo O'Brien (disambiguation), various
 * Leonora O'Brien, Irish pharmacist and entrepreneur
 * Leslie O'Brien
 * Liam O'Brien (disambiguation), various
 * Lucy O'Brien
 * Luke O'Brien

M

 * Margaret O'Brien
 * Mariah O'Brien
 * Mark O'Brien (disambiguation), various
 * Mary Eileen O'Brien, American academic administrator
 * Matthew O'Brien (1814-1855), Irish mathematician
 * Maureen O'Brien
 * Michael O'Brien (disambiguation), various
 * Michele O'Brien
 * Mick O'Brien (disambiguation), various
 * Mike O'Brien (hurler)
 * Miles O'Brien (disambiguation), various
 * Mollie O'Brien

N

 * Niall O'Brien (disambiguation), various
 * Nick O'Brien

O

 * Olivia O'Brien (born 1999), American singer and songwriter

P

 * Paddy O'Brien (disambiguation), various
 * Parry O'Brien
 * Patricia Salas O'Brien (born 1958), Peruvian sociologist and Minister of Education
 * Patrick O'Brien (disambiguation), for people with forename Patrick or Pat
 * Pat O'Brien (disambiguation), various
 * Paul O'Brien (disambiguation), various
 * Peter O'Brien (disambiguation), various
 * Phil O'Brien (disambiguation), several people

R

 * Raymond O'Brien, American Roman Catholic priest
 * Richard O'Brien (disambiguation), various
 * Riley O'Brien, American baseball player
 * Robert O'Brien (disambiguation), various
 * Rory Brien
 * Ron O'Brien (disambiguation), various
 * Roy O'Brien

S

 * Scott O'Brien
 * Sean O'Brien (disambiguation)
 * Sean Patrick O'Brien (1988-2023), American professional wrestling referee
 * Shane O'Brien (disambiguation), various
 * Shannon O'Brien
 * Sicele O'Brien, Irish aviator
 * Simon O'Brien (disambiguation), various
 * Soledad O'Brien, American television journalist
 * Stephen O'Brien, UK conservative politician for Eddisbury
 * Stuart O'Brien (1906–2004), American film editor
 * Stuart O'Brien (stage) (1833–1883), Australian actor

T

 * Terence O'Brien (disambiguation), various
 * Thomas O'Brien (disambiguation), various
 * Tim O'Brien (disambiguation), various
 * Timothy O'Brien (theatre designer) (1929–2022), British theatre designer
 * Timothy O'Brien (endocrinologist), Irish professor
 * Timothy L. O'Brien (born 1961), American journalist
 * Tina O'Brien (born 1983), English actress
 * Tom O'Brien (actor) (b. 1965), American film actor
 * Tom O'Brien (American football) (b. 1948), American college football coach at North Carolina State University
 * Tom O'Brien (outfielder) (1873–1901), baseball outfielder
 * Tom O'Brien (second baseman) (1860–1921), 19th century baseball player
 * Tom O'Brien (trade unionist) (1900–1970), British trade unionist and Member of Parliament
 * Tommy O'Brien (baseball) (1918–1978), baseball outfielder

U

 * Una O'Brien, British civil servant

V

 * Vincent O'Brien (disambiguation), various
 * Virginia O'Brien

W

 * Walter O'Brien, Computer expert and Irish businessman
 * Walter A. O'Brien, American Progressive Party politician
 * William O'Brien (disambiguation), various
 * Willis H. O'Brien (1886–1962), American motion picture special effects pioneer

Z

 * Zach O'Brien, professional ice hockey player

As first or middle names

 * O'Brien Alston (b. 1965), American former football linebacker
 * O'Brien Schofield (b. 1987), American former football linebacker
 * O'Brien Smith (c. 1756 – 1811), Irish-American political figure

Fictional people named O'Brien

 * O'Brien, a character in George Orwell's novel Nineteen Eighty-Four
 * Lady Cassandra O'Brien, fictional character, Doctor Who antagonist
 * Chloe O'Brian, a fictional character played by actress Mary Lynn Rajskub on the US television series 24
 * Graham O'Brien, a companion of the Thirteenth Doctor in the BBC series Doctor Who
 * Keiko O'Brien, fictional character, wife of Miles O'Brien in Star Trek: The Next Generation and Deep Space Nine
 * Miles O'Brien, a fictional character in Star Trek: The Next Generation and Deep Space Nine
 * Sarah O'Brien, a fictional character on the ITV series Downton Abbey
 * Shelia O'Brian, a character from the animated TV series Dungeons and Dragons
 * Mr. O'Brien, Mrs. O'Brien and Jack O'Brien, fictional characters in The Tree of Life film