Biddlesden is a village and civil parish within Aylesbury Vale district in north west Buckinghamshire, England on the border with Northamptonshire. It is situated about 3 miles ENE of Brackley, Northamptonshire and five miles north west of Buckingham. The River Ouse forms part of the western boundary of the parish, separating the village from Northamptonshire. The ancient royal forest of Whittlewood extended to the northern border of the village.