It is a resident breeder in the Caribbean coastal lowlands from southeastern Mexico to central Panama, but is absent from El Salvador and southern Guatemala.

Adult males are mainly chestnut with a blackish head and rump, and a tail which is bright yellow apart from two dark central feathers.

There is a bare blue cheek patch and a pink wattle, the iris is brown, and the long bill is black at the base with a red tip.

In total body mass, the males are 100% bigger than the females, which is a 2:1 body-to-mass ratio and makes the Montezuma oropendola one of the most sexually-dimorphic birds in the world.

Webster et al. observed that males defend sexually-receptive females, suggesting that Montezuma oropendolas have a female-defence mating system.

[3] The "unforgettable"[4] song of the male Montezuma oropendola is given during the bowing display, and consists of a conversational bubbling followed by loud gurgles, tic-tic-glik-glak-GLUUuuuuu.

It is a colonial breeder and only the females build hanging woven nest of fibres and vines, 60–180 cm (24–71 in) long, in a tree that is up to 30 meters high.

The female lays two dark-spotted white or buff eggs, and she incubates them without the male until they hatch in 15 days; the young fledge in 30.