It lives in and around subtropical and temperate forests in the Andes of Colombia, Ecuador, Bolivia, and Peru at elevations of 1500–3350 m. It is seen in pairs or in groups of 3-6 individuals.

It forages mostly on the upper half of short trees and eats fruits and insects.

Its nest is made of mosses and ferns, and its eggs are gray with light purple-grey dots.

The grass-green tanager was formally described in 1840 by the French ornithologist Auguste Boissonneau from a specimen collected near Bogotá in Colombia.

[2][3] The species is now the only member of the genus Chlorornis that was introduced in 1850 by the German naturalist Ludwig Reichenbach.