Patriarch Nicholas I

Patriarch Nicholas I may refer to:


 * Patriarch Nicholas I of Antioch, ruled in 826–834
 * Patriarch Nicholas I of Constantinople (Nicholas Mystikos), Ecumenical Patriarch in 901–907 and 912–925
 * Patriarch Nicholas I of Alexandria, Greek Patriarch of Alexandria in 1210–1243
 * Nicholas I Zaya, patriarch of the Chaldean Catholic Church in 1839–1847