Abstract: Based on the hourly monitoring data of PM_2.5 from 10 state-controlled air quality monitoring stations in Guiyang from 2013 to 2017, the air pollution level and its spatial-temporal distribution characteristics in Guiyang were analyzed. The results show that: (1) the average concentration of PM_2.5 in Guiyang is 36. 14 ug·m-3 in 5 years, which is basically within the national air quality secondary standard, and the pollution degree is relatively light; (2) the winter concentration of PM_2.5 in Guiyang is the highest in a year, the highest concentration occurs in December, the lowest concentration in summer, and the lowest concentration occurs in July; (3) The effect of meteorological factors on PM_2.5 concentration was significant, especially in seasonal conditions. PM_2.5 concentration was positively correlated with solar radiation, sunshine hours and air pressure, and negatively correlated with precipitation, relative humidity, wind speed and air temperature. Solar radiation had the greatest impact on PM_2.5 in summer, sunshine hours had the greatest impact on PM_2.5 in spring, and temperature had a significant negative correlation with PM_2.5 concentration in summer and autumn. The correlation between spring precipitation and PM_2.5 is more significant. Wind speed in summer and winter has a significant negative correlation with PM_2.5 concentration.