Michael O'Neill may refer to:
- Michael O'Neill (diplomat) (born 1967), British diplomat
- Michael O'Neill (academic) (1953–2018), English poet and academic
- Michael O'Neill (actor) (born 1951), American actor
- Michael O'Neill (educator), pioneer in non-profit management education
- Michael O'Neill (footballer) (born 1969), Northern Irish football player and manager
- Michael O'Neill (politician) (1909–1976), Irish politician
- Michael E. O'Neill (born 1946), chairman of Citigroup
- Mike O'Neill (basketball) (born 1928), American basketball player
- Mike O'Neill (baseball) (1877–1959), Irish-born American starting pitcher and left fielder in Major League Baseball
- Mike O'Neill (ice hockey) (born 1967), Canadian professional ice hockey goaltender
- Mike O'Neill (lacrosse), three-time All-American lacrosse player
- Mike O'Neill (musician) (born 1970), Canadian singer-songwriter
- Mike O'Neill (rugby league) (born 1960), English rugby league footballer of the 1970s, 1980s and 1990s
- Mike O'Neill, winner of a 2006 Costume Designers Guild Award
- Michael O'Neill, founder of the Informed Medical Options Party, a minor political party in Australia
- Mikey O'Neill (footballer) (born 2004), English footballer
See also
edit- Michael O'Neal (born 1951), American lawyer and Republican politician
- Mickey O'Neil (1900–1964), American professional baseball
- Mickey O'Neil, fictional character from the 2000 film Snatch