Abstract: In recent years, the aerosol pollution over the Pearl River Delta (PRD) region is getting worse, resulting in haze weather with visibility decreasing and air quality deterioration. The surface layer transport condition such as airflow is closely related to the dilution and diffusion of atmospheric pollutants. By using statistic method under a set standard based on dataset from 466 Guangdong provincial surface automatic weather stations, Guangzhou operational weather stations, visibility data of PRD's atmospheric component observational network, and PM₁₀ data of PRD's urban environmental observational network, typical haze weather and cleaning weather processes are analyzed in 2004 and 2005. The surface wind and its effect on heavy haze and cleaning weather processes are analyzed using Vector Sum Technique. The zonal circulation over Eastern Asia in favorite haze season in 2004 is stronger than that in 2005. The year with weak zonal circulation has marked exchange between the north and the south, allowing much cold air to cross Nanling Mountain to reach PRD, the accompanying strong wind is favor for the diffusion of the pollutants. In the year with strong zonal circulation cold air has little chance to cross Nanling Mountain to reach PRD so that the pollutants accumulate much easily. The haze weather over PRD has the regional features with the most likely occurrences in dry season and the least in rainy season. The haze processes often happen from October to next April, while cleaning processes often occur in the seasons when typhoon or cold air is prone to occurrence. Compared to 2004, the frequency of still wind is lower and the wind speed in dry season is larger in 2005, those factors are not favor for the form of haze weather. Analysis using Vector Sum Technique shows that regional haze process is closely related to the regional still wind process by which formation of airflow stagnation area is led to, while cleaning process is related to strong advection transport.