The black-bellied chinchilla is docile, mainly active at night, and does not hibernate. It feeds on plants and also eats a small amount of insects.

The black-bellied chinchilla is small and fat, with short limbs and neck, and a cylindrical shape. The body is brown on the back, and the belly is gray-black. Its skull is small and flat with clear sutures. The forehead is slightly higher and the back is lower. It mostly inhabits forests and forest margins in the middle and high mountains above 800 meters above sea level, especially the forest belts or thickets under shady slopes and forests as habitat sites.