In this study, fine particles were sampled at three environmental monitoring stations at all seasons in Yixing, the concentration of their chemical compositions were determined. The source of PM2.5 was analyzed by the chemical mass balance (CMB) model. Results showed that the annual average concentration of PM2.5 in Yixing was 37.5 μg/m3. The concentration of 53.1 μg/m3 in winter was the highest. The main chemical compositions of PM2.5 were SO2-4, NO-3, OC, EC, NH+4, Cl-, Ca, Na and Al, and the main sources were secondary sulfate (21.0%), secondary organic aerosol (14.9%), secondary nitrate (14.1%) and coal fired power plant (8.0%). With local emission inventory, the main sources of emission were from industry (33.1%), coal combustion (23.1%), vehicle exhaust (17.6%), dust (9.3%) and other sources (16.9%) according to secondary source apportionment. The key point of reducing particulate pollution was controlling the emission from industry, coal combustion and vehicle. |