The chestnut-backed owlet (Glaucidium castanotum) (often misspelled Glaucidium castanonotum), is an owl which is endemic to Sri Lanka. This species is a part of the larger grouping of owls known as typical owls, Strigidae, which contains most of the smaller owl species. This species was formerly considered to be a subspecies of the jungle owlet.
The chestnut-backed owlet is small and stocky, measuring 19 cm in length. It resembles the jungle owlet in shape, size and appearance but the upperparts, scapulars and wing coverts are mainly chestnut brown, with darker barring. The underparts are white with blackish shaft-streaks. The facial disc is mainly brown and the eyes are yellow. There is a white neckband. Sexes are similar in appearance, with no sexual dimorphism.