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By means of the PM10 data from 2006 to 2008 obtained at Yan’an, the concentration level and variation are analyzed, and their relationship with meteorological conditions is studied. The annual mean mass concentration of PM10 is 153 μg/m3 at Yan’an, which is two times higher than the limit value of 70 μg/m3 according to the Class 2 Standard of the National Ambient Air Quality Standard (NAAQS). The regional background level of PM10 has an average value of 109 μg/m3, which contributes significantly to the ambient PM10 level in Yan’an. The mass concentration of PM10 is the highest in spring, then in winter, autumn and summer. The number of days with the mass PM10 concentration exceeding the Class 2 limit value (150 μg/m3) of NAAQS accounts for 40% in the whole year and 66% in spring. The diurnal change of PM10 shows a double peak double valley distribution curve, and PM10 concentration has significant negative correlation with the diurnal variation of wind speeds. The scavenging efficiency of 1 mm rainfall on PM10 decreases successively in winter, spring, autumn and summer. The mass concentration of PM10 is the highest under westerly winds, but the highest accumulated contribution to PM10 is the southwest winds, about 40 to 50 μg/m3 higher than that in the other wind directions.