They are recognized by their green plumage, black beak and characteristic blue feathers arranged like a crown on their head.

The blue-crowned hanging parrot was formally described in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae.

The specific epithet galgulus is an unidentified small bird described by the Roman author Pliny the Elder as hanging by its feet.

Adult females plumage is duller green in color compared to the males, they do not have the red throat mark and have a less apparent or absent blue crown on the head and lack yellow feathers on their lower back.

[10] The blue-crowned hanging parrot is distributed throughout southern Thailand, western Malaysia, Singapore, Sumatra, Borneo and other nearby islands.

The birds climb or fly up tall trees and will hang by either both feet or only one foot and will fluff their feathers and tuck their head and neck into their body.

The parrot's green plumage and hanging sleeping position imitates leaves among trees to camouflage themselves among the foliage.

Young and sick birds are unable to hang and will perch sitting upright to sleep with their head turned to one side while tucked into the back feathers.

The pair's bond is maintained in this species through courtship feeding where the male will regurgitate food and offer it to a female.

[9][15] Hanging parrots eat mainly fruits, such as papaya and rambutan, in the wild but will also feed on palm oil nuts, seeds, nectar, and fresh flowers.

Young birds usually use their mandibles to nibble and break off pieces of food when perching and will flick their heads rapidly to remove the pulp after extracting its juice.