The black-eared fairy (Heliothryx auritus) is a species of hummingbird in the subfamily Polytminae, the mangoes.

It is found in every mainland South American country except Argentina, Chile, Paraguay, and Uruguay.

The black-eared fairy was formally described in 1788 by the German naturalist Johann Friedrich Gmelin in his revised and expanded edition of Carl Linnaeus's Systema Naturae.

The female is similar but has no purple on the face, its throat and breast have grayish dots, and the three outer pairs of tail feathers have a black band at their base.

The male H. a. phainolaemus has a variable green throat and chin and the female does not have the nominate's gray spots on the underparts.

"[11] The nominate subspecies of black-eared fairy is found from southeastern Colombia and eastern Ecuador through northern Brazil north of the Amazon River to northeastern Venezuela and through the Guianas.

[11] The International Union for Conservation of Nature has assessed the black-eared fairy as being of Least Concern, though its population size is not known and believed to be decreasing.