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Based on the hourly PM2.5 concentration data of 10 environmental monitoring stations of Guiyang in 2013 and 2014, the pollution characteristics of PM2.5in 2013 and 2014 are described. In combination with the comparative analysis of Guiyang hourly precipitation data, the change features of precipitation and particulate pollution are discussed. The results show: The annual mean value of PM2.5 was about 33 to 55 μg/m3; the monthly pollution concentration values were high in autumn, winter, and early spring, but low in summer. The daily variation of PM2.5 concentrations showed the typical structure with double peaks, and the value was high in morning and evening. When there is rainfall, average concentration is nearly 20% lower than that without precipitation annually. The PM2.5concentrations in rainy days were lower obviously than those without rain. In the rainy days, the concentrations of PM2.5 were reduced obviously especially during night and morning session, which was associated with the precipitation characteristics of Guiyang. Compared with the precipitation less than 1 mm, the removal and inhibition effect of precipitation greater than 1 mm was more remarkable.