title: Patriarch Dionysius I
text: # Patriarch Dionysius I
  
  Patriarch Dionysius I may refer to:
  
  * Patriarch Dionysius I Telmaharoyo, head of the Syriac Orthodox Church in 818–845
  * Dionysius I of Constantinople, Ecumenical Patriarch in 1466–1471 and 1488–1490
  