Abstract: This paper determined the vertical distribution of the mass concentration and particle size distribution of the respirable particles in Autumn of Shijiazhuang,. The results show that the diameter with the largest content is 0.2μm～1.0μm and the BET area of respirable particles in the atmosphere is 3536.2～4396.06 m2/kg. The PM2.5 to PM10 ratio ranged from 71.28％ to 81.14％. The accumulative content of the very small respirable particles is increasing with the sampling height. Moreover, PM2.5 and PM10 is logarithmic increasing with the sampling height, The D50 is >1μm when the sampling height ≤1.5m and D50 is <1μm when the sampling height >1.5m. For the dry depositions at different sampling heights, exhibit that D50 is 9.66～13.78μm and the BET area is 336.55～790.06 m2/kg and PM2.5/PM10 is19.46～22.47％ and D98 is 34.93～53.48μm。

Key words: Respirable particles, mass concentration, particle size distribution, vertical distribution