In the present article, the environmental impacts of the Iraq-Kuwait war (1991) on the ecological condition and fisheries resources of the northern part of the Persian Gulf, during years 2001-2002 were studied. The investigated area included the whole stretch of the Iranian domain of the Persian Gulf from northwestern waters of the Khuzestan province to northeastern waters of the Hormuzgan province. Petroleum hydrocarbons and oil-originated heavy metals of Ni, V, Pb and Cd were measured in water, sediment and fish tissue, and also various physicochemical parameters were analyzed and recorded in the summer and winter. Distribution pattern of Hopane (C29-C35) in sediment and demersal fish tissues were similar to that found in the Kuwait’s crude oil samples. The highest concentrations of TPH and PAH were recorded in the sediment samples from Khuzestan coasts (the closest Iranian province to the Gulf war zone), their concentrations showed a decreasing trend eastward as distanced from Khuzestan. The concentration of Cd, Pb and Ni in the sediment samples was also found to be considerably higher than the global baseline value and that of RSA and ERL guidelines. Results indicated the presence of Kuwaiti crude oil in sediments as a Result of the Persian Gulf war (1991). On the basis of these results, the ecosystem of the Persian Gulf was exposed to long-term adverse environmental impacts by severe oil pollution.