Mulligan is a surname originating from Ireland, coming from the Irish Ó Maolagain literally meaning "grandson of the bald man".
- Andy Mulligan (author), English writer
- Blackjack Mulligan, American professional wrestler and American football player
- Buck Mulligan, given name Malachi Mulligan, fictional character in James Joyce's novel Ulysses
- Carey Mulligan, British actress
- Charles Mulligan, American sculptor
- Cynthia Mulligan, Canadian television personality
- David Mulligan, New Zealand association football (soccer) player
- Eddie Mulligan, American baseball player
- Gary Mulligan, Irish association football (soccer) player
- Geoff Mulligan, American Computer Scientist, IoT developer
- Gerry Mulligan, American musician
- Hercules Mulligan, a spy for the patriot forces in the American Revolutionary War
- Colonel James A. Mulligan, American Civil War soldier
- James Hillary Mulligan, American judge, politician, and poet
- James Venture Mulligan, Australian bushman and prospector
- John Mulligan, new wave musician with Fashion (1978–84)
- John Mulligan (baseball), played for the Washington Nationals in 1884
- Kevin Mulligan, British philosopher
- Leith Mulligan, Australian sports journalist
- Marty Mulligan, Australian tennis player
- Mary Mulligan, Scottish politician
- Colonel Michael Mulligan, American military prosecutor
- Nancy Mulligan, song by Ed Sheeran
- Noel Mulligan, Australian rugby league footballer
- Richard Mulligan (1932–2000), American actor
- Richard Mulligan (footballer), New Zealand association football (soccer) player
- Robert Mulligan, American film director
- Rosemary Mulligan, American politician
- Terry David Mulligan, Canadian actor
- William Hughes Mulligan, American judge
- Mulligan's, a Dublin pub