This paper is intended to analyze the impact of regional transport of PM （particulate matter） on Xiamen city. The characteristics of clustering trajectory in seasons of the years from 2015 to 2016 in Xiamen were statistically analyzed by using the clustering backward trajectory and the PSCF （potential source contribution function） method. Relatively analysis suggested that regarding PM transport the north and local were of great proportion in spring, autumn and winter, while in summer the south and local paths were the main. The high concentrations of PM2.5occurred via the transport paths of west and local as PM pollution level got worse than the level of ＇fine＇ or the ＇slight pollution＇ in terms of the national environmental standard, and apart from the local accumulation of PM the pollution in winter was featured by the transport path from north to Xiamen, while in spring the pollutant air mass was transported from Hunan, Jiangxi and Fujian provinces; fine particle pollutants mainly came from local source and via the north, and coarse particles were transported through long distance from northwest China. The analytic results by PSCF indicated that the areas of the YRD （Yangtze River Delta）, NCP （North China Plain） and the local region were the main PM sources that impact Xiamen in spring and winter, and transport from the Pearl River Delta （PRD） to Xiamen was the most important pollution path during autumn. In conclusion, the PM pollution of Xiamen city where the air is relatively clean was characterized with apparent seasonal difference being affected by the synthetic factors of multi-sourced and multi-scale.
Environmental Science and Technology