John V may refer to:
- John the Merciful, Patriarch of Alexandria from 606 to 616
- Patriarch John V of Constantinople, Patriarch from 669 to 675
- Pope John V, Pope from 685 to his death in 686
- John V the Historian, Catholicos of Armenia from 897 to 925
- John V of Gaeta (c. 1010–1040)
- John V of Naples, Duke from 1036 to 1042
- John V Palaiologos (1332–1391), Byzantine Emperor from 1341
- John V, Duke of Brittany (1339–1399)
- John V, Duke of Mecklenburg (1418–1443)
- John V, Prince of Anhalt-Zerbst (1504–1551)
- John V of Portugal (1689–1750), King of Portugal and the Algarves
- John 5 (guitarist)