Seventy-four species of mammals are cited after two surveys trips to Calilegua National Park, Ledesma and Valle Grande Departaments, Province of Jujuy, Argentina. The information was completed with a deep bibliography research and personal comments. The mammal community presents differences in its composition in relation with the altitude and the phytogeographical structure. In the transition forest (500 m altitude) occurs the majority of the species (62%), with an important chacoan fauna ingression. Excepting Rodentia, all the orders show decreased values to higher altitudes. Systematic and taxonomic information of the species are analyzed.