The article discusses a study on the predatory behavior of margay, Leopardus wiedii. These solitary and nocturnal wild cats are easily recognized for their physical characteristics, which include prominent eyes, salient snout, big paws and long tail. The study conducted in the Atlantic Forest in Brazil revealed that margays practice opportunistic predation on bats. From June 19 to 20, 2003, five bats were found to be injured while one was dead. Observation revealed that canines of a small cat may have caused the injuries.