St Mary's School was an independent day and boarding girls' school located in Wantage, Oxfordshire, England. In 2007 it merged with Heathfield School to become Heathfield St Mary's School (later reverted to Heathfield) and the Wantage site was closed. It was affiliated with the Church of England and had close ties with its founding order, the Community of St Mary the Virgin. It was predominantly a boarding school.