Ioannes IV

Ioannes IV (, Iōannēs D΄) may refer to:

• Patriarch John IV of Constantinople (died in 595)
• John IV, Archbishop of Ohrid (c. 1088 – 1163/64)
• John IV Laskaris (1250–c. 1305)
• John IV Megas Komnenos (c. 1403–1459), emperor of Trebizond

See also

• John IV (disambiguation)