This study was conducted to determine the seasonal prevalence, and intensity of Allocreadium isoporum, which was founded as an endoparasite in Oxynoemacheilus tigris. A total of 136 host fishes was captured seasonally from Murat River near province of Bingol, Turkey, between from December 2012 to November 2013. During the study totally 209 parasites were recorded. The seasonal prevalence, and intensity, seasonal variation of sex and size of the host fish, the highest and lowest infection density, and larval and mature forms of A. isoporum ratio of the distribution were investigated. This study has been conducted to determine the infection parameters, of A. isoporum in O. tigris for the first time. [ABSTRACT FROM AUTHOR]