John IV
- Ioannes IV (disambiguation)
- Ivan IV of Russia
- Jan IV of Nassau
- Jan IV of Oświęcim
- Jean, Count of Paris
- Johann IV (disambiguation)
- John 4
- John Ernest IV, Duke of Saxe-Coburg-Saalfeld
- John IV (bishop of Naples)
- John IV Laskaris
- John IV of Armenia
- John IV of Chalon-Arlay
- John IV of Constantinople
- John IV of Ethiopia
- John IV of Gaeta
- John IV of Naples
- John IV of Ohrid
- John IV of Portugal
- John IV of Trebizond
- John IV, Count of Armagnac
- John IV, Count of Katzenelnbogen
- John IV, Count of Nassau-Idstein
- John IV, Count of Soissons
- John IV, Count of Sponheim-Starkenburg
- John IV, Duke of Bavaria
- John IV, Duke of Brabant
- John IV, Duke of Brittany
- John IV, Duke of Krnov
- John IV, Duke of Mecklenburg
- John IV, Duke of Saxe-Lauenburg
- John IV, Landgrave of Leuchtenberg
- John IV, Lord of Arkel
- John IV, Marquess of Montferrat
- Patriarch John IV of Alexandria
- Pope John IV
