Michael O'Brien
Michael O'Brien or Mike O'Brien is the name of the following people:
- Michael O'Brien (historian) (1948-2015), British historian
- Michael O'Brien (swimmer) ( Mike O'Brien ; born 1965), American swimmer
- Michael J. O'Brien (politician, 1939) (born 1939), American politician
- Michael J. O'Brien (archaeologist) (born 1950), American archaeologist
- Michael J. O'Brien (politician, 1955) (born 1955), American politician
- Mike O'Brien (actor) (born 1976), American actor and comedian
- Mike O'Brien (politician, 1954) (born 1954), British politician
- Mike O'Brien (Politician, Canada) , Canadian politician
- Mike O'Brien (hurling player) , (born 1978), Irish hurling player
