St Cynfarwy's Church is a medieval parish church in Llechgynfarwy, Anglesey, north Wales. The first church in the vicinity was established by St Cynfarwy (a 7th-century saint about whom little is known) in about 630, but no structure from that time survives. The present building contains a 12th-century baptismal font, indicating the presence of a church at that time, although extensive rebuilding in 1867 removed the datable features of the previous edifice.