Parasites of an invasive species, the raccoon dog (Nyctereutes procyonoides) from western Poland were investigated to clarify poorly known ecological key aspects of the species. The research was conducted in two study areas: the Ujście Warty National Park and the Bogdaniec Forestry District. Intestinal samples were collected from the intestinal tracks of 39 dead animals and 51 faecal samples were collected in all seasons from latrines of raccoon dogs. Macro-parasites, their eggs and protozoan parasites were investigated to assess the taxonomic composition of parasites, the level of infection and the risk of potential transfer of dangerous parasites from raccoon dogs to people and native species. Among parasites potentially dangerous for human and native mammal species, Toxocara canis was found in the intestines and T. canis eggs, Cryptosporidium sp. oocysts and Entamoeba sp. cysts were identified in faecal samples. Sarcoptic mange was observed in the skin of two animals, whereas Diptera larvae (probably from the family Gasterophilidae) were found in the intestines of two other animals. This latter finding is very interesting, because Gasterophilidae are the typical parasites in horses and ungulates, but so far were never found in raccoon dogs.