As an integrated part of management plan against the elevated air pollution, typical monitored emission inventory was presented for metropolitan area of Beijing in 1999. The air pollutants of concern were fine particulate matters (PM10), sulfur dioxide (SO2), and nitrogen oxides (NOx). Emissions of these air pollutants were estimated by suitable emission factors and evaluated in three categories of point, area and line sources. Total yearly mean emissions in the studied area were estimated as 103,298 tons of PM10, 209,914 tons of SO2, 225,394 tons of NOx. To assess the air quality, Industrial Source Complex-Short Term (ISCST3) dispersion model was applied by combining measured emissions and meteorological data with 1 hour temporal and 1km×1km spatial resolution. Validity of model was verified by comparing the monitored data from Beijing's Environmental Protection Bureau with the model values predicted. Demonstrated by Geographical Information System (GIS), results indicate that the levels of PM10, SO2, and NOx were serious and endangered the regional human health. While area source accounted for 83.8% of PM 10 concentration distribution and 79.2% of SO2 concentration distribution respectively, line source contributed 73.5% of NOx concentration distribution. It reveals insight on emission control priorities and future implementations of effective control technology.