The causes of persistent haze pollution in Jiujiang City from the end of November to the beginning of December 2016 are analyzed. The results show that there were three main long-distance paths to transport fine particles to Jiujiang. The upstream guide wind and the local static weather conditions made local pollutants superimposed on the particulate matter. The first source emission and two conversion of different inorganic pollutants contributed to the increase in the concentration of particles in Jiujiang. High temperature and high humidity could promote the formation of two organic particles. But when temperature was low in winter,the increase of energy consumption made local source emission increase. The high molecular weight semi-volatile organic compounds in the air were adsorbed on the surface of the particles,and the haze was gradually formed through the process of hygroscopic growth and the aging of particles. Jiujiang's natural landform,the " valley wind" circulation effect of dominant wind,and the radiation effect of aerosol were favorable for the accumulation of pollutants in Jiujiang.