The Potos flavus is a nocturnal mammal that lives in neotropical forests from Central America to South America. A study of four cases of rabies in Potos flavus was conducted; these occurred in April 2012 in the Madre de Dios region in Peru and were collected as part of epidemiological surveillance. The analysis performed in the regional reference laboratory of Madre de Dios determined the presence of the rabies virus antigen in three of the brain tissue samples. Results were verified in the Laboratory of Viral Zoonoses of the Peruvian National Institute of Health by direct immunofluorescence. The typification did not identify any of the known variants in bats or dogs. The occurrence of four cases of rabies in Potos flavus adds evidence of the emergence of a new reservoir of the rabies virus previously reported in the same region in 2007.