John O'Callaghan may refer to:
- John O'Callaghan (Medal of Honor) (1850–1899), American soldier and Medal of Honor recipient
- John O'Callaghan (politician) (died 1913), secretary of the United Irish League
- John O'Callaghan (musician), Irish musician and DJ
- Liam McCarthy and John D. O'Callaghan, BT Young Scientists of the Year and EU Young Scientists of the Year, 2009
- John Cornelius O'Callaghan (1805–1883), Irish historian and writer
- John Joseph O'Callaghan (1838–1905), Irish architect
- John O'Callaghan (singer), vocalist and guitarist of The Maine
- John O'Callaghan (American football) (born 1964), American football player in the 1987 Seattle Seahawks season
See also
Topics referred to by the same termThis disambiguation page lists articles about people with the same name. If an internal link led you here, you may wish to change the link to point directly to the intended article. Category: