Within this master thesis, the local distribution of the hazel dormouse (Muscardinus avellanarius) in Southern Carinthia (Austria) is investigated in different habitat types along an altitudinal gradient. Furthermore, the acceptance of four different types of man-made nest boxes is studied. The hazel dormouse is a protected species of the Annex IV of the EU habitat directive. It is widespread in Carinthia, but detailed data on regional distribution are still absent. Within this project, the presence of hazel dormice was studied in 10 forest sites in the surroundings of Ferlach by searching for gnawed hazel nuts. Furthermore, in two of those sites, four different types of nest boxes were exposed from the beginning of May to the beginning of September 2013 and controlled every two weeks. On each site ten plots were studied, with two boxes per type and per plot. Half of the boxes were impregnated to see, if dormice prefer impregnated boxes or not. The study of the gnawed hazel nuts showed that hazel dormice were present in 9 out of 10 forest sites. Nest boxes, nest tubes and herbage nests were used by hazel dormice, while they avoided shelter caves with large entrance holes. The impregnation did not show any influence on the utilization of the different types of nest boxes. Hazel dormice preferred nest tubes, as they were used during the whole activity period, but breeding only took place in nest boxes. Herbage nest were exclusively colonized during July and August. However, the use of herbage nests may also provide important information on the presence of hazel dormice. Furthermore, the utilization of nest boxes is dependent on the number of wooden plant species and the number of food plant species in the surrounding of the nest boxes.