Gilla na Naemh Ua Duinn (1102 – 17 December 1160) was an Irish poet, historian, and cleric.
The Annals of the Four Masters describe him as:
"lector of Inis-Clothrann, a paragon in history and poetry, and a good speaker, sent his spirit to his heavenly patrimony, amid a choir of angels, on the 17th of December, in the fifty-eighth year of his age."
Inis Clothran is an island located in the northern part of Lough Ree, on the River Shannon. It contains the remains of a monastery of which Ua Duinn was lector.