Charterhouse Square is a garden square, a pentagonal space, in Farringdon, in the London Borough of Islington, and close to the former Smithfield Meat Market. The square is the largest courtyard or yard associated with the London Charterhouse, mostly formed of Tudor and Stuart architecture restored after the London Blitz. The square adjoins other buildings including a small school. It lies between Charterhouse Street, Carthusian Street and the main Charterhouse complex of buildings south of Clerkenwell Road. The complex includes a Chapel, Tudor Great Hall, Great Chamber, the Barts and The London School of Medicine and Dentistry and a 40-resident almshouse.

Farringdon is an area in London and is located in the London Borough of Islington. It lies just north of the border with the City of London in Central London and close to Holborn. The term is used to describe the area around Farringdon station.