The transport process of pollution gases under different weather situation are simulated at Mountain Huang on 26 April and 2 May 2008 by using a new generation atmospheric chemistry transfer model WRF-Chem.Results show that,in sunny conditions,the pollution gases are transported vertically from downhill to uphill by mountain-valley breeze circulation,the transport of pollutants in the surrounding areas has less effect on the volume fraction of pollutants at Guangmingding,and new particle formation is the main source of atmospheric aerosols.However,in cloudy conditions,the pollution gases are transported vertically to the uphill by turbulent diffusion in boundary layer,the short range transport has much effect on the volume fraction of pollutants at Guangmingding in the nighttime,and the aerosol particles mainly come from the ground transport.