The parasitic fauna of freshwater fishes of the Warri River, Delta State, Nigeria, with reference to their prevalence, intensity and differences in metazoan parasites between fish sexes, was investigated. A total of 85fish samples comprising of 21 Tilapia zillii (Cichlidae: Perciformes), 23 Synodontisclarias (Mochokidae: Siluriformes), 23 Chrysichthys nigrodigitatus (Claroteidae: Siluriformes), 16 Hepsetus odoe (Hepsetidae: Characiformes)and 2 Clarias anguillaris (Clariidae: Siluriformes) collected from the Warri River, Delta State, Nigeria, were subjected to parasitological examination.The overall metazoan parasite prevalence was 32.9%. The metazoan parasites recovered were mainly the acanthocephalans: Neoechinorhynchusprolixum, Pomphorhynchus spp., Acanthocephalus spp. and unidentified acanthocephalan, and nematodes: Camallanus polypteri, Capillariapterophylli, C. cichlasomae, Procamallanus laeviconchus, Philometroides africanus and Railletnema synodontis. Although the acanthocephalans constituted 75.6% and nematodes 22.2% of the parasites recovered, thenematodes had the highest prevalence (23.5%) compared to the acanthocephalans (9.4%). Similarly, variable prevalences were observed for the other metazoan parasite taxa recovered, namely trematoda; Clinostomumcomplanatum (1.2%), Leech; Pisciola geometra (2.4%) and Crustaceans (1.2%). The highest parasite prevalence (39.1%) was observed in S. clarias, while the least (23.8%) was observed in T. zillii. Generally, the prevalenceof parasites was higher in female (35.7%) than in the males (31.6%), although statistically no significant difference was observed in the prevalence by sex (X2 = 0.145, P = 0.807). The relatively high overall parasite prevalence in fishes inhabiting the Warri River may be attributed to the relatively high level of pollution.Ovo istraživanje bavi se proučavanjem parazitofaune slatkovodnih riba iz rijeke Warri u državi Delti u Nigeriji s obzirom nazastupljenost, intenzitet pojave i razlike u višestaničnim parazitima kod različitih spolova. Parazitološkom pregledu podvrgnutoje ukupno 85 jedinki ribe iz rijeke Warri u državi Delti u Nigeriji: 21 Tilapia zillii (Cichlidae: Perciformes), 23 Synodontisclarias (Mochokidae: Siluriformes), 23 Chrysichthys nigrodigitatus(Claroteidae: Siluriformes), 16 Hepsetus odoe (Hepsetidae: Characiformes) i dvije Clarias anguillaris (Clariidae: Siluriformes).Ukupna zastupljenost višestaničnih parazita bila je 32,9%. Otkriveni višestanični paraziti uglavnom su bili akantocefali, Neoechinorhynchus prolixum, Pomphorhynchus spp., Acanthocephalus spp., a isto tako i neidentificirani akantocefali i nematode, Camallanus polypteri, Capillaria pterophylli,C. cichlasomae, Procamallanus laeviconchus, Philometroides africanus i Railletnema synodontis. Među otkrivenim parazitimaakantocefala je bilo 75,6%, a nematoda 22,2%, no usprkos manjem postotku, nematode su imale veću zastupljenost (23,5%) u usporedbi s akantocefalima (9,4%). Isto tako, praćena je i zastupljenost drugog višestaničnog parazita– trematoda (metilja): Clinostomum complanatum (1,2%), zatim pijavica (Leech); Pisciola geometra (2,4%) i račića (Crustaceans)(1,2%). Najveća zastupljenost parazita zabilježena je kod S. Clarias, a najmanja (23,8%) kod T. zillii. Sveukupno gledajući, zastupljenost parazita bila je veća kod ženki (35,7%)nego kod mužjaka (31,6%), iako statistički nema velike razlike u zastupljenosti parazita po spolu ( 2 = 0,145, P = 0,807). Relativno visoka ukupna zastupljenost parazita kod riba možese pripisati relativno visokoj razini onečišćenja
