Abstract：To obtain the aerosols distribution as a function of aerodynamic diameter at different points in gobi area of northwestern China,the corresponding count and mass median diameter were calculated.The results indicate that the mass concentration of aerosols in sampling points is between 0.03 and 0.1 mg/m³.The size distribution of aerosols has 2 peaks that the first locates at about 0.05 μm and the second at about 3 μm.The difference of the size distribution at different points is mainly shown as the difference of the second peak area.Most count median diameter of samples is smaller than 1 μm,and the mass median diameter is locating between 2 and 5 μm.

Keywords：gobi area;aerosol;mass concentration;particle size distribution