The aim of this study is to evaluate the contamination status of Iraqi rivers in the north of the Tigris river (Tikrit city) and the middle region of Euphrates (Babylon Governorate). In this study As, Zn, Fe, Pb, and Cu in the muscle tissue of carp fish were measured. The results show that the concentration of arsenic in the fish muscles in the middle region was 425.05 ppm higher than its concentration of about 192.25 ppm in fish muscle in the Tigris river with statistical significance (P<0.05). Which it causes histopathological changes characterized by Zenker's necrosis in skeletal muscle and infiltration of inflammatory cells with edema additional to edematous dermatitis. Other heavy metals in fish muscle were less than in fish muscles which agreement with the international legislation limits. Also, there were positive correlation ships between Zn and Pb and between Cu and Zn. While negative correlation has been detected between arsenic and both Pb and Zn. This study is concluded that the accumulation of heavy metals causes histological changes in fish muscle provides an opportunity to assess fish health as well as information on possible health hazards coming from their environment.