Houlihan or O'Houlihan (Irish: Ó hUallacháin; feminine Ní Uallacháin) is a surname of Irish Gaelic origin, from the Irish uallach meaning "proud". Notable people with the surname include:

• Adam Houlihan (born 1978), former Australian rules footballer
• Christopher Houlihan (born 1987), American concert organist
• Con Houlihan (1925–2012), Irish sportswriter
• Damian Houlihan (born 1975), former Australian rules footballer
• Gerard Houlihan, Irish retired Gaelic footballer
• Jim Houlihan (1898–1967), Irish sportsperson
• Joan Houlihan, American poet
• John C. Houlihan (1910–1986), American politician, the 43rd mayor of Oakland, California
• John J. Houlihan (1923–2003), American politician, Illinois state representative
• Mike Houlihan (born 1969), retired Irish sportsperson
• Pat Houlihan (1929–2006), English snooker player
• Patrick Houlihan (1889–1963), Irish politician
• Ryan Houlihan (born 1982), Australian rules footballer
• Shelby Houlihan (born 1993), American middle-distance runner
• Tim Houlihan (born 1989), Australian rules footballer
• Timmy Houlihan (born 1982), Irish sportsperson

See also

• Houlihan's, an American restaurant and bar chain
• Houlihan Lokey, independent, advisory-focused, global investment bank
• Houlihan Stadium or Tampa Stadium, a sports venue in Tampa, Florida
• Houlihan Smith & Company, investment banking firm
• Jim Houlihan Park at Jack Coffey Field, a baseball venue on the Rose Hill campus of Fordham University in Bronx, New York
• Cathleen ni Houlihan, one-act play written by Irish playwright William Butler Yeats
• Kathleen Ni Houlihan, a mythical symbol and emblem of Irish nationalism found in literature and art
• Margaret "Hot Lips" Houlihan, a fictional character in the M*A*S*H franchise
• In cattle roping the houlihan is a one-swing flip shot at a calf traveling in front of you from left to right
• Holohan, an alternative spelling
• Hooligan
• Houlahan
• Wes Hoolahan
• O'Houlihan (dynasty)