Large mammals, especially felids such as Mountain Lion, Puma concolor (Linnaeus, 1771), are disappearing from their original habitats, due to the loss of natural areas and hunting, especially in the metropolitan regions. In the city of Rio de Janeiro, Brazil, P. concolor had not been observed for almost a century, despite the city having forest fragments as large as 10,000 ha. Here we present records that confirm the reappearance of this species in the city of Rio de Janeiro, where it has been considered extirpated.