Air pollution is the presence of undesirable substances in concentration, duration and frequency that has adverse effects on human health and welfare. SO2 and NOx are considered one of the air pollutants that have acute effects on human and animals. Consumption of fossil fuel in point sources and industrial processes are the greatest sources of this pollutants. Therefore, we can assume power plants as the major source emission of this pollutants. Although evaluating and simulation of spatial distribution of air pollutants are essential for quality management and metropolitan planning. In this study, by using AERMOD software, we modeling the distribution of NOx and SO2 emitted from Shahid Montazeri and Islamabad Isfahan power plants during the mazut and gas burning time. Also Arc GIS 9.3 software and aggregating operation of maps are used to provide the distribution map of accumulation concentration of pollutants. Assessment of amount of pollutants produced in this two process indicate a sever decrease of this two pollutants, that in Mazut burning pose amount of SO2 provides is 12.86 and NOx is equal to 4.81 ton per hour, whereas in gas burning pose 27.46 Kg per hour producing SO2 and 2.24 ton per hour for NOx. The results show that accumulative concentration of SO2 in both power plants in all modeling periods (1 24 hour) higher and in the gas burning pose very low from that and it was below the regulation of Department of Environment and EPA. It’s also indicated that with shifting from Mazut to gas burning decrease the emission of NOx, although the severity of NOx patterns in comparison to SO2 patterns in both time periods is much lower. In hourly time period concentration in both Mazut (554 µg/m 3 ) and gas burning (374 µg/m 3 ) is higher than the standard set (188 µg/m 3 ). But the annual period of this pollutant in both cases is less than standards. Incorporation map of land use and pollutants showed that unauthorized distribution of one – hour SO2 concentration is cover approximately entire the area except the Baharestan town. Also in 24 hour SO2 distribution maps, unauthorized distribution is only seen around both power stations. For NOx pollutants, the unauthorized distributions in both gas and oil burning estate involves the land use around both power plant. Incorporation map of regional population distribution with pollutants distribution indicated that the population affected by Mazut burning one and 24 – hour SO2 concentration are respectively 2.897.520 and 50.945. Also the population affected by unauthorized concentration of one – hour NOx Mazut and gas burning respectively are 35.011 and 8.927. Because the region’s total population is about 3.145.982, the result shows that more than 92% of population in one – hour SO2 concentration map of oil burning are affected by unauthorized concentration