Abstract: Using the hourly observation data of precipitation, wind, and PM_2.5 in Tai'an from 2018 to 2019, the impacts of precipitation and wind on PM_2.5 concentration as well as the source of PM_2.5 were analyzed.The results showed that precipitation has a certain scavenging effect on PM_2.5.The average mass concentration of PM_2.5 on rainy days is about 7.2% lower than that on non-rainy days, especially in autumn and winter.The scavenging rate of PM_2.5 by precipitation is related to precipitation intensity, initial PM_2.5 concentration before precipitation, and precipitation duration.The scavenging rate of PM_2.5 is higher than 40% when the precipitation intensity is greater than 4 mm·h^-1.The PM_2.5 concentration tends to rebound under conditions of precipitation intensity < 2 mm·h^-1, or the initial PM_2.5 concentration < 75 μg·m^-3 and precipitation intensity < 1 mm·h^-1, or the initial PM_2.5 concentration within the range of 75-100 μg·m^-3 and precipitation duration < 5 h.Different wind directions and wind speeds show different impacts on the scavenging of haze particles in Tai'an.The west-southwesterly wind and the east-northeasterly wind are more likely to cause haze pollution in the Tai'an area.During heavy pollution, the southerly winds > 5 m·s^-1 and the northerly winds > 3 m·s^-1 can effectively remove pollutants.PM_2.5 is mainly transported from Guangxi-Hu'nan-Jiangxi provinces, southern Anhui province, and northern Zhejiang province to Tai'an by southwesterly airflows, and less contribution is from the local emissions.