It is named after its characteristic long, curved bill that develops ridges, or wreaths, on the casque of the upper mandible in adults.

The wreathed hornbill ranges across the foothills and evergreen forests of Northeast India and Bhutan to Bangladesh, Southeast Asia and the Greater Sunda Islands.

The female's gular skin is blue, whereas the male's is bright yellow; his neck is white and his nape dark reddish passing into black.

[8] Sexual dimorphism in the colouration of plumage and inflatable gular skin is less pronounced in young wreathed hornbills, but becomes more apparent as both sexes mature.

Hornbill casques contain foamy air-filled cavities surrounded by multiple layers of keratin tiles that act as an external shell.

[9] It is hypothesized that specialized casque characteristics evolved due to multiple selection pressures, including its use for vocalization enhancement, physical pounding, mating displays, and as visual cues for age and social status.

[12][13] The wreathed hornbill inhabits tropical evergreen forests in the region from southern Bhutan, Northeast India, Bangladesh and through mainland Southeast Asia to Indonesia, where it is restricted to Sumatra, Java, Borneo and a few smaller islands.

[17] In Arunachal Pradesh, the wreathed hornbill density is much lower in habitats where local people hunt, ranging from 2.9 to 9.02 birds/km2 (7.5 to 23.4 birds/sq mi).

[9] When calling, the wreathed hornbill displays its brightly coloured throat sac by sharply thrusting its head backwards and upwards.

The seed dispersal behaviour of the wreathed hornbill plays a critical role in maintaining tropical forest diversity.

It nests in the cavities of large trees located in coastal forests, illegally logged areas, or among foothills up to an elevation of 2,560 m (8,400 ft).

[28] Females use droppings or mud to cover the nest hole to protect the clutch and fledglings from predators but leave a gap large enough for males to deliver food.

[6] Major threats to wreathed hornbill populations include hunting, use of pesticides, illegal logging and habitat fragmentation.

[28] In Arunachal Pradesh, the local Mishmi and Adi people shoot 50–70 wreathed hornbills during the migratory season; they eat their meat, use their gizzards as medicine to cure stomach problems, their feathers to decorate their homes and their casques to adorn their headgear.