The pollution characteristics of organic carbon(OC)and elemental carbon(EC)in PM2.5 were studied by analyzing the mass concentration of organic carbon and elemental carbon during autumn and winter in Shenyang.It was showed that the concentration of EC and OC in the ambient air was higher in autumn of Shenyang area.The average mass concentrations of second organic carbon(SOC)in autumn and winter were 8.28-14.81 μg/mn3 and 6.98-11.59 μg/m3 respectively,and the secondary pollution was relatively serious.Based on the principal component analysis of the carbon components,it was found that the carbon components in autumn and winter were mainly from biomass and coal combustion emissions and gasoline vehicle exhaust.The correlation between K+and OC,EC or SOC in winter was better,indicating that K+had the certain homology with OC,EC and SOC.It was a good correlation between OC and EC in winter,and the pollution sources in Shenyang area were relatively consistent.