[1] The KDN complex is the last large remaining rainforest in Sri Lanka other than Sinharaja.

This biosphere reserve harbors many plants and animal species endemic to Sri Lanka.

The vegetation of KDN complex represents Sri Lanka lowland rain forests.

[3][4] The floral communities dominated by Shorea-Dipterocarpus-Mesua (Sinhalese "Doona-Hora-Na") are common in emergent layer of the forest.

They include Coscinium fenestratum (Sinhalese "Weniwelgata"), Salacia reticulata ("Kothala Himbutu"), and Tinospora cordifolia ("Rasakinda").

[4] Out of 26 endemic birds of Sri Lanka, 20 of them can be seen in KDN forest complex.

[7] Forestry, collection of non-timber products, rice cultivation, tea, rubber and cinnamon plantations, animal husbandry and other forms of agriculture and cottage industries are main economic activities take place around the forest.

[8] Green-billed coucal, Sri Lanka blue magpie, ashy-headed laughingthrush and white-faced starling are the bird species listed as endangered.