The yellow-bellied seedeater (Sporophila nigricollis) is a species of bird in the family Thraupidae, formerly placed with the New World sparrows in the Emberizidae.

The "hooded seedeater" was a proposed bird species described by Austrian ornithologist August von Pelzeln as Spermophila melanops in 1870. The only known individual was heavily moulted and caught in October 1823 from a flock of other seedeater species at the edge of a lake 15 kilometres north of Registro do Araguaia, Brazil. It is now considered to be either an abnormal specimen of the yellow-bellied seedeater or a hybrid. The bird had a black crest and throat, the upperparts were olive, and the underparts showed a dingy buff. In contrast, a typical yellow-bellied seedeater has pale yellow underparts and the black colouring extends to the upper breast.

The yellow-bellied seedeater is found in Central and South America from Costa Rica to Bolivia. Its natural habitats are subtropical or tropical high-altitude shrubland, pastureland, and heavily degraded former forest.

One study in Brazil estimated that 16,800 yellow-bellied seedeaters are illegally caught and sold as pets annually.