EN
Introduction. The european eel is one of the major fishing objects of the Russian fishery zone of the Vistula Lagoon (Baltic Sea). This is the reason that its parasite fauna was studied within 1998-2005. Material and methods. Totally 142 individuals of 35-81 cm in length were examined. The parasites collected from various organs were fixed and processed according to commonly accepted methods. Results. Twenty two parasite species representing the following higher taxa: Coccidia (2), Oligohymenophorea (2), Myxosporea (5), Monogenea (1), Cestoda (2), Trematoda (2), Nematoda (4), Acanthocephala (2), and Crustacea (2) were recovered. The following main features of the eel parasitofauna were determined: high specificity, predominance of the parasites with simple life cycle, the presence of three invader species (Anguillicola crassus, Pseudodactylogyrus anguillae, and Paratenuisentis ambiguus). The latter species was found in the Vistula Lagoon for the first time