A strong sandstorm of North China in 2002 was simulated with the Models3/CMAQ system newly developed by US EPA. The pollution source data were based on the AC EAsia and TRACEP Experiments in 2002, and the particulate emission data were estimated by the visibility range from MICAPS observations. The results show th at, (1) the spatiotemporal evolvement and the mutual relationship of gas eous pollutants are consistent with the common regulation derived from observati ons. (2) The simulation of coarse PM also reflects the observational facts: The diurnal trend of both fine and coarse PM first falls and then raises; The PM so urce before SDS is near surface emission while the PM source after SDS becomes upperair’s transportation of dust; Pollution of coarse PM is dominant; （3） This air qual ity model system can be used for further development on dust aerosols.