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During the course of a major sandstorm from April 17 to April 23,2008 in the Taklimakan Desert,data pertaining to the mass concentrations of different-sized atmospheric particulate matter were observed continuously with Grimm 1.108,Thermo RP 1400a,TSP,and CAWS-600 instruments.The results showed that:(1) during the entire sandstorm process there were some differences between the daily mean particle concentration peaks and the hourly mean particle concentration peaks because the actual sandstorm lasted for only about 4 hr,whereas more particles were accumulated in the floating dust days before and after the actual sandstorm; (2) the intensity of the sandstorm was enhanced with the increase of wind speed,and this was related to the peak mass concentrations of atmospheric particulate matter;,the wind speed directly affected the concentration of atmospheric particulate matter:the higher the wind speed,the higher the mass concentration (＞0.23 μm was 39,496.5 μg/m3,and ＞20.0 μm was 5,390.7μg/m3); (3) the concentration changes of PM10 and TSP were also related to the course and intensity of the sandstorm; and (4) the mass concentration of atmospheric particulate matter had the following sequence during the dust weather:clear day ＜ floating dust ＜ floating and blowing dust ＜sandstorm.Temperature,relative humidity,and barometric pressure are important factors affecting the strength of storms,which could also indirectly affect the concentration change of atmospheric particulate matter.