The yellow-bellied sunbird-asity (Neodrepanis hypoxantha) is a small species of passerine bird from the asity family. The male has black upper parts with a bluish sheen and yellow underparts, and is sometimes known simply as the yellow-bellied asity. It is found only in montane rainforests of Madagascar where it feeds on nectar that it sips from flowers, defending a good nectar source from other nectar-feeding birds. It is listed by the International Union for Conservation of Nature as "vulnerable" due to the diminution and fragmentation of its forest habitat.