Houlihan or O'Houlihan (Irish: Ó hUallacháin; feminine Ní Uallacháin) is a surname of Irish Gaelic origin. 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), the 43rd mayor of Oakland, California
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
Tim Houlihan (born 1989), Australian rules footballer
Timmy Houlihan (born 1982), Irish sportsperson
