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According to the monitoring reports of recent years from the Beijing Environment Protection Bureau,PM10 remains in a high level,being the predominant air pollutant in over 90% days of a whole year.SO_2 pollution has been controlled to certain extent and NO_2 pollution is improved slightly with a slowly decreasing trend generally.Comparison and analysis is conducted on the three dust weather events happened in Beijing in spring of 2004,and in combination with the variation of the air pollutant concentrations(or index) in March in Beijing,the influence of dust weather on air quality in Beijing is discussed.The results provide references for air quality forecasting under dust weather in Beijing.