Nisaetus cirrhatus ceylanensis is a subspecies of the changeable hawk-eagle (Nisaetus cirrhatus). It is a large, slender raptor, typically dark brown above with a boldly streaked underside, thinly-barred tail, and long feathered legs. This subspecies is endemic to Sri Lanka and has a proportionally longer crest than the nominate species. Like many tropical forest raptors, it is primarily an ambush predator, using concealing foliage to still-hunt before swiftly pouncing on its prey. Its diet is varied, consisting of small birds, mammals, reptiles, and other vertebrates.

The breeding season for the changeable hawk-eagle runs from November to June, peaking between January and March. During this time, the species builds a large, sturdy stick nest capable of withstanding high winds and monsoons. The female lays a single egg, which she incubates alone for approximately 60 days.