Charles O'Brien
Charles O'Brien may refer to:
- Charles O'Brien, 5th Viscount Clare
- Charles O'Brien, 6th Viscount Clare, Irish military officer in French service
- Charles O'Brien, 7th Viscount Clare
- Charles O'Brien (colonial administrator), British Governor of the Seychelles and Barbados
- Charles O'Brien (cricketer), Australian cricketer
- Charles F. X. O'Brien, United States Representative from New Jersey
- Charles H. O'Brien, State Senator and judge from Tennessee, United States
- Charles M. O'Brien, Member of the Legislative Assembly of Alberta, Canada
- Charles P. O'Brien, American research scientist
- Charlie O'Brien, retired American baseball player
- Charlie O'Brien (racing driver), Australian racing driver
- Charles O'Brien (unionist), American labor union organizer