Northaw Great Wood is a 223.6-hectare (553-acre) biological Site of Special Scientific Interest (SSSI) near Cuffley in Hertfordshire, England.

Part of the site is managed by Hertfordshire County Council as a schools' park.

Closure of the canopy has led to the disappearance of open woodland birds such as nightingales and tree pipits, but the management plan for the wood aims to restore biodiversity.

[5] The site has one of the county's most extensive areas of ancient hornbeam woodland, with other trees including oak and silver birch.

[1] There is access from the Ridgeway in Cuffley and facilities include a car park and toilets.