The manuscripts total some 200 volumes, ranging from the 11th century Greek manuscripts to 20th century correspondence. There are some 40 mediaeval manuscripts, including a 13th century psalter belonging to Archbishop Meopham, a 15th century York breviary, and Wycliffite New and Old Testaments. Later material includes the minutes of the Presbyterian Provincial Assembly of London, 1647-60, an augmentation order book of the Committee for the Reformation of the Universities, 1650-2, and works of the mathematician Nathaniel Torporley (d. 1632).

Finding aids: 

Sion College manuscripts card index, available in the Library

C.J. Kitching, 'Summary list of the Latin and English manuscripts in Sion College Library London' (typescript, Royal Commission on Historical Manuscripts, 1990) 
[Compiled before the manuscripts were transferred to Lambeth Palace Library. Does not include manuscripts in languages other than Latin and English.] 

Ker, N.R. Medieval manuscripts in British Libraries vol.1: London, (Oxford, 1969: pp. 263-91).
Includes manuscripts sold by the College in 1977 - see below.

Pickering, O.S. & O'Mara, V.M. The Index of Middle English Prose: handlist 13.  Manuscripts in Lambeth Palace Library including those formerly in Sion College Library (Cambridge, 1999).

The following manuscripts did not come to Lambeth Palace Library when the collection was transferred : 
English MSS
E 15 (Thomas Bray) sold at Sotheby's 13/6/1977 (lot 76)
E 21 (Joye's school minute book) - at Guildhall Library c.1953
E 23 (Chaucer) sold at Sotheby's 13/6/1977 (lot 73)
E 41 (Bennet & Clements booksellers memorandum book) sold at Sotheby's 13/6/1977 (lot 75)
E 76 (Langland Piers Plowman) sold at Sotheby's 13/6/1977 (lot 74)
Latin MSS
L8 (Syon Abbey processional) - missing in 1932.  Now Syon Abbey, South Brent, Devon: MS 1
L9 (Suetonius) sold at Sotheby's 13/6/1977 (lot 71)
L21 (Suetonius) sold at Sotheby's 13/6/1977 (lot 70)
L28 (Hugo Folieto & the Bestiary of Humphrey Duke of Gloucester) sold at Sotheby's 13/6/1977 (lot 72) - now Getty Museum
L34 (Merchant Taylor's School admissions register 1644-1662) - at Merchant Taylor's since 1930