Abstract: In order to study NOx,SOxemission performance of pulverized coal industrial boiler,the main processes of the system including coal combustion,heat transfer of the flue gas,water evaporation in the drum and ash separation were modeled by engineering software Aspen Plus. The sensitivity analysis tool in Aspen Plus was used to discuss the pollutant characteristics influenced by air volume,coal flow rate,carbon conversion and furnace gauge pressure. The results showed that pollutant emission reached the maximum when the air volume was 21300 m3/ h,the excess air coefficient was 1. 82,or the coal flow rate was 42. 5 kg / min. Carbon conversion promoted the emission of NOxsignificantly,while the affects on SOxwas not significant. The furnace gauge pressure had no effects on pollutant emission when it was in the zone of negative pressure.