It is found in the Andes of northern Peru (Amazonas and Cajamarca Regions) and southern Ecuador (Zamora-Chinchipe Province).

[2][3][4] Records from Colombia reflect the vagueness of the stated type locality, "Neu-Granada", encompassing territory part of several present-day countries.

[4] Atelopus pachydermus occurs near streams in páramo and sub-páramo at an elevation of about 2,600 m (8,500 ft) above sea level.

Breeding takes place in streams, and the species seems to depend on a permanent source of water.

The status of this population is unknown, but extensive agricultural activity is taking place within the park.