Postăvaru Mountains are one of the most important touristic areas of Romania and Brașov County. Here, the most important mountain resorts of Romania, Poiana Brașov is located, known for its numerous ski paths. Also, the high accessibility of the area is given by the developed road network across the mountains. The aim of this study is to analyse the degree of natural habitat fragmentation, caused mainly by touristic activities and grazing that lead to deforestation and the growth of anthropic surfaces. GIS tools, by ArcGIS 10.1 software, were used to analyse the way that human activities caused the natural forest habitat fragmentation. By applying the proposed methodology, the Habitat Fragmentation Density Index, of which values reveal the critical areas regarding the loss of natural habitat and assert the degree of habitat fragmentation caused by the considered anthropic elements (ski paths, roads, pastures and built areas), was computed and spatially modeled.