According to the data of 14 atmospheric precipitation monitoring stations of Jian hydrology bureau in 2018，the chemical characteristics and pollution sources of atmospheric precipitation in Jian were analyzed from the aspects of precipitation pH value，ion molar concentration and its time variation trend，ion correlation and precipitation pollution type.The analysis shows that sulfur pollution is more serious than nitrogen oxide pollution in the precipitation of Jian city，and the precipitation type is mainly coal burning or sulfuric acid pollution.Since Ca2+ and NH4+ have a good neutralization effect on SO42 - and NO3-，which are mainly acid-causing anions，and Ca2 + has a more obvious neutralization effect on precipitation，SO42 - and NO3- are mainly acid-causing anions and do not cause acid rain pollution.The type of atmospheric precipitation in Jian city is alkaline precipitation.The analysis of the above monitoring data is expected to provide technical support for the active implementation of river length system and the development and utilization of water resources.