St Peirio's Church is a small disused medieval church, in Rhosbeirio, Anglesey, north Wales. It is unclear when a church was first established on this site, although it has been said that this happened in about 605. The current structure, which may date from the 15th century, has been restored in the 18th and 19th centuries. It ceased being used for services some years ago and has been boarded up.