In recent decades in Europe there has been a decline in the population of European brown hare (Lepus europaeus L.). Diseases, including parasitoses, are one of the factors considered to be the cause for the phenomenon. In this connection the aim of the present work was to update the data on the composition and distribution of endoparasites of this small mammal in Bulgaria against the background of the situation in Europe. Thirty sets of abdominal organs and forty seven faecal samples of hares from different regions of the country were investigated for presence of parasites. The faeces were analyzed with the coproscopical methods of Fulleborn, serial sedimentations, and the modified Baermann technique. Helminthological necropsies of the abdominal organs were carried out through the common technique. Parasites of the following taxa were established: Trematoda (Dicrocoelium dendriticum), Cestoda (Cysticercus pisiformis, Mosgovoyia pectinata), Nematoda (Trichuris sylvilagi, Strongylidae, Strongyloides sp., Protostrongylus spp.), Protozoa (Eimeria spp.) and Arthropoda (Pentastomum dentatum). Strongyloides sp. is reported for the first time as a part of the parasite fauna of the European brown hare in Bulgaria. Trichuris sylvilagi was the most prevalent parasite (63.3%), followed by gastrointestinal strongylids (57.43%), Eimeria spp. (55.3%), Protostrongylus spp. and Strongyloides sp. (31.9%), D. dendriticum (14.3%), C. pisiformis (10%), and M. pectinata (6.67%). The studies showed that eimeriid coccidia, gastrointestinal strongylids, and trichurids are the most common endoparasites among the population of the European brown hare both in Bulgaria and the European continent.