St Donats is a village and community in the Vale of Glamorgan in south Wales, located just west of the small town of Llantwit Major. The community includes the village of Marcross and the hamlets of Monknash and East and West Monkton. It is named after the 6th-century saint, Dunwyd, a friend of Saint Cadoc. It had a population of 732 in 2011.