The Great, or Main Cloister appears to have been built along with other claustral buildings immediately after the church was completed in c. 1181, perhaps replacing earlier buildings. The large cloister set around a central garth was almost square in plan measuring 21.6m by 21.2m. The cloister was of common design with a narrow low wall supporting an arcade which separated the cloister walk (3.20m wide) from the central garth, or garden (13.6m by 14m in size). Evidence of benched seating has been found built along the west and north cloister walks.

A laver or wash basin built on a pedestal foundation was situated against the cloister wall of the refectory doorway and appears to date to the late fourteenth century when the cloister was rebuilt

A massive re-building programme occurred within the main cloister during the late 14th to early 15th century. The earlier tiled floor was ripped up and the arcade demolished and four new arcade walls, forming the re-built cloister, were constructed. The alignment of the new cloister was slightly askew from the former, to accommodate the massive north buttress built to support the north side of the church following the earthquake of 1381.

The cloister was demolished at the Dissolution in 1538.

Hicks, M., 1989, 'St. Gregory's Priory: The Church and Conventual Buildings' (Article in serial). SKE30366.

Hicks, A. & Hicks, M., 2001, St. Gregory's Priory, Northgate, Canterbury, Excavations 1988-1991 (Monograph). SKE30367.