The faunal lists of cave, epigaeic and soil species of Araneae (73 species), Collembola (61 species), Orthoptera (35 epigaeic species) and Coleoptera (127 species) collected in the years 2005 and 2006 from the Rodnei Mountains Biosphere Reserve are presented. Among these, eight species: Rugathodes bellicosus (Araneae, Theridiidae), Glyphesis servulus (Araneae, Linyphiidae), Incestophantes frigidus (Araneae, Linyphiidae), Gnaphosa badia (Araneae, Gnaphosidae), Eusphalerum pallens (Coleoptera, Staphylinidae), Cryptophagus corticinus (Coleoptera, Cryptophagidae), Otiorrhynchus scaber (Coleoptera, Curculionidae) Thamnurgus varipes (Coleoptera, Scolytidae), are for the first time recorded for the Romanian fauna. The presence of other species in the Romanian fauna is confirmed and new data on the local distribution of some rare or protected species are given. For the Pietrosul Mare Scientific Reserve (the core area of the Biosphere Reserve) quantitative and qualitative samplings from all altitudinal biotic zones, were carried out with the aim to observe the altitudinal gradient in the faunal structure. A brief zoogeographic analysis is presented