In this study a parasitological investigation on 238 samples of Neogobius species from the south-east of Caspian Sea was carried out. The samples including Neogobius melanostomus (35), N. fluviatilis pallasi (103), N. kessleri gorlap (70) and N. bathybius (30) were seasonally seined by beach net during one year (summer 2006-spring 2007), fixed in 10 % buffer formalinand transferred to the labor...