Marlborough Royal Free Grammar School, previously known as Marlborough Grammar School and King Edward's School, Marlborough, was a grammar school in the town of Marlborough, in Wiltshire, England, founded in 1550. Originally for boys only, the school became co-educational in 1906. Over a period of more than four hundred years, it had a number of homes around Marlborough. In 1975 it was closed, and its final buildings were re-used for the new St John's Marlborough comprehensive school.