Gilla an Choimded Ó Duillénnáin (died 1229/30) was an Irish cleric.
Ó Duillénnáin was a coarb or erenagh of Saint Feichin, though at what foundation is uncertain. Places connected with Féchín's cult include: Fore Abbey (Co. Westmeath), Cong Abbey (Co. Mayo), Omey Island (Co. Galway), Ardoilén/High Island (Co. Galway), Inishmaan (Co. Galway), Claddaghduff (Co. Galway), Cleggan (Co. Galway) and Termonfeckin (Co. Louth).
The Annals of Connacht record his death, sub anno 1229:
The Annals of Ulster contain more detail: