Ivan III may refer to:
Ivan III Nelipac (died 1434), viceroy of Croatia Ivan III of Russia (1440–1505), grand prince of Moscow and later sovereign of all Russia Ivan III of Ryazan, grand prince of Ryazan (1427–1456) Ivan III Draskovic (1595 or 1603 – 1648), Croato-Hungarian warrior and statesman, Palatine of Hungary Ivan Asen III, tsar of Bulgaria 1279–1280