Abstract: Using air pollutant data and meteorological data from Anshun, Guizhou province, the characteristics of air quality and pollutants from 2015 to 2019 in Anshun were analyzed.Using HYSPLIT backward trajectory model, along with GDAS data and PM_2.5 concentration data, seasonal transport pathways and pollution trajectories were analyzed as well.The potential source contribution function (PSCF) and concentration-weighted trajectory (CWT) were applied to evaluate the vertical and horizontal variations of transport pathways in all days with PM_2.5 polluted (i.e., concentrations above 75 μg·m^-3).The results show that PM_2.5 was the major pollutant in the urban area of Anshun and air transport accounted for a large proportion for this in winter, with the major pathways to the northeast and south of Guizhou province.Polluted airmass from the northeast direction led to PM_2.5 pollution, during which the tracks were mainly distributed at the height of 880-980 hPa.The areas with high potential source values were mainly concentrated over the whole area of Guiyang, Bijie Zhijin County, Qianxi County, Jinsha County, etc., whereas the areas with high contribution values were mainly concentrated in Ziyun County, Zhenning County, Bijie Zhijin County, Dafang County, etc.