Peter III may refer to:

Politics

  • Peter III of Bulgaria (ruled in 1072)
  • Peter III of Aragon (1239–1285)
  • Peter III of Arborea (died 1347)
  • Peter III Aaron (died 1467)
  • Pedro III of Kongo (ruler in 1669)
  • Peter III of Russia (1728–1762)
  • Peter III of Portugal (1717–1786)
  • Peter III (cat) (1947-1964)

Religion

  • Pope Peter III of Alexandria (477–489)
  • Peter III of Raqqa, Syriac Orthodox Patriarch of Antioch in 581–591
  • Peter III of Antioch Greek Orthodox Patriarch of Antioch
  • Peter III (bishop of Lugo) (r. from 1113 until 1133)
  • Peter III, Pope Peter III of the schismatic Palmarian Catholic Church

See also

  • Pedro III (disambiguation)