Abstract Historical and recent data on Portuguese mammals are presented in this paper, occurring on the mainland and/or in the Azores and Madeira Atlantic islands. Nowadays, 95 species of mammals are known in Portugal, of which only one (Nyctalus azoreum) is an endemic species and three others (Pipistrellus maderensis, Microtus cabrerae and Lynx pardina) are exclusive for Portugal and Spain. Moreover, two other species, Mustela vison and Sciurus vulgaris are recent records for the Portuguese fauna, the first due to an accidental introduction and the second resulting from a recolonization by Spanish populations. Of the remaining species, around 50% (46 species) are threatened in different degrees, 34.8% (16 species) being considered endangered or vulnerable. Mammals extinct in Portugal are the Gerês goat (Capra pyrenaica lusitanica) and the bear (Ursus arctos).