Parsonage Down (grid reference SU050412) is a 188.6 hectare biological Site of Special Scientific Interest in Wiltshire, notified in 1971.
The site is a national nature reserve.
Following the introduction of the Countryside and Rights of Way Act, the whole of the site was designated "access land" and is therefore open to public access.
The site has the largest population of Burnt Orchid (Neotinea ustulata) in northwest Europe.
Coordinates: 51°10′12″N 1°55′47″W / 51.17002°N 1.92986°W