The library at St Mary's was completely refurbished in 1998. It has a large collection of subject material, along with an extensive reference collection, newspapers, journals and a very popular fiction section. There are plenty of computers, including laptops which provide access to a wealth of on-line material via the school network and internet.

The library is run by two qualified librarians and allows access from 8am to 6.45pm each weekday plus Saturday mornings for all age groups. Year 11 and Sixth Form may use the library until 10pm each evening.