Leaota Mountains have not been studied nearly at all until our researches, from the perspective of the invertebrate fauna. Subsequently to these studies carried out in the north-western sector of this Massive, we have identified 248 taxons at the level of species and other 5, at the level of the genre. The cause of this remarkable biodiversity is represented by the diversified geological and geomorphological composure, alongside with a multitude of micro-climates types, all these taking shape through the development of diverse environmental conditions which are thus responsible for the existence of a very wide invertebrate fauna diversity also, which is though not fully known. In Leaota Mountains, the Natura 2000 ROSCI0102 site was created, with a surface of only 1393 hectares (Antofie and Pop, 2013); when it was created, the existing invertebrate species in these mountains were unknown. The identification, through our researches, of a large number of species, of a endemicity degree of more than 9%, as well as of some new and rare invertebrate species for the Romanian fauna, corroborated with the need of also protecting the karstic relief in this area, leads us to the conclusion that the extension of the protected area status for the north western sector of Leaota Mountains also is extremely necessary.