John O'Brien

• Ambrose O'Brien
• Cinders O'Brien
• Fireflies (TV series)
• Jack O'Brien (disambiguation)
• Jack O'Brien (jazz pianist)
• John B. O'Brien
• John F. O'Brien
• John F. O'Brien (secretary of state)
• John H. O'Brien
• John J. O'Brien (civil servant)
• John J. O'Brien (commissioner)
• John L. O'Brien
• John O'Brien (Australian Army officer)
• John O'Brien (Australian politician)
• John O'Brien (British politician)
• John O'Brien (Canadian politician)
• John O'Brien (Dublin footballer)
• John O'Brien (Irish cricketer)
• John O'Brien (Irish politician)
• John O'Brien (Louth footballer)
• John O'Brien (New Zealand politician)
• John O'Brien (Ohio politician)
• John O'Brien (admiral)
• John O'Brien (advocate)
• John O'Brien (basketball, born 1888)
• John O'Brien (basketball, born 1916)
• John O'Brien (bishop)
• John O'Brien (boxer)
• John O'Brien (businessman)
• John O'Brien (cricketer, born 1961)
• John O'Brien (filmmaker)
• John O'Brien (hurler)
• John O'Brien (marine artist)
• John O'Brien (novelist)
• John O'Brien (outfielder)
• John O'Brien (poet)
• John O'Brien (priest)
• John O'Brien (rower)
• John O'Brien (screenwriter)
• John O'Brien (second baseman)
• John O'Brien (soccer)
• John O'Brien (tennis)
• John O'Brien (water polo)
• John P. O'Brien
• John T. Raymond
• John Thomond O'Brien
• Johnny O'Brien
• Jon O'Brien
• Joseph John O'Brien
• Terence O'Brien (colonial governor)