This article is about Puffin Island in Wales. See also Puffin Island, Scilly Isles .

Puffin Island (Welsh: Ynys Seiriol) is a small island lying east of Anglesey in Wales. Until the sixth century it was home to the Penmon Priory , led by Saint Seiriol . It is now known for its bird population, including razorbills, guillemots and puffins.