Two hundred forty-seven species of parasites from Iranian freshwater fishes are presented in this synopsis. The parasites were recorded from infestations in fish from different parts of the country and summarized according to host species, organs were the parasite infestations occurred, province, faunal region and reference numbers. The following aspects of parasite infestations were also discussed: records of the most predominant parasites, the richest regions of parasite fauna, records of parasites according to province and the most severely infected fish species and finally host specificity in terms of exotic or endemic fish