Abstract:This paper samples PM2.5 and analyzes its components in January, April, July, and October of 2013 and 2014. The results showed that the annual concentrations of PM2.5 are 170.4 μg·m-3 and 144.0 μg·m-3. The annual concentration of PM2.5 decreases 15.5%, compared to 2013. The orders of OC are winter(31.7 μg·m-3)>autumn(24.4 μg·m-3)>spring(9.1 μg·m-3)>spring(5.6 μg·m-3). And the orders of SOC are autumn (13.1 μg·m-3)>winter(8.8 μg·m-3)>spring(2.4 μg·m-3)>summer(2.0 μg·m-3), which account for 24.6%、34.6%、43.9%, and 27.7% of OC, respectively. The annual scatter coefficient is 524.9 Mm-1 by using the IMPROVE equation. The scatter coefficient of winter is 872.6 Mm-1, which is notable higher than 564.8 Mm-1 of autumn, 333.9 Mm-1 of summer and 328.4 Mm-1 of spring. Ammonium sulfate is the largest contributor, which contributed to 33.9% of scatter coefficient, followed by 25.3% of ammonium nitrate, 20.2% of organic matter, 15.4% of PM2.5-10, and 5.7% of dust.