We report the first fossil record of the Mephitidae family in Chile, which consists of a large portion of the cranium. The material was discovered in the Pilauco paleontological site, Osorno, Chile (40 degrees 39'S0-73 degrees 07'W) and was deposited during the late Pleistocene (Lujanense age). The previous records of fossil and present day South American Mephitidae have been included in the genus Conepatus Gray, 1837. The published fossil record comes from paleontological sites in Argentina, Bolivia, Brasil, Peru and Venezuela, which cover most of the present distribution. However, there are many areas that lack records, such as Chile. Using the comparative method based on cranium measures and applied to present and fossil specimens of the above mentioned family, our results show that the discovered cranium belongs to Mephitidae and specifically to the genus Conepatus. Furthermore, the paleodistribution of the genus is extended with the first Pleistocene fossil record for Chile.