Abstract: The present work introduces a numerical simulationapproach to calculate the concentration profiles of CO, NOx, andSOx, and study the effects of combustion temperature and pulverizedcoal particle size on NO formation during pulverized coal combustion coupledwith detailed chemical reaction mechanism and CFD software. The numericaldata are validated with the experimental ones. The results show that thereis significant effect of the combustion temperature and not obvious effectof coal particle size on the NO formation. Increasing temperature obviouslyenhances NO concentration. There might exist different temperature pointscorresponding to the fast rate of NO formation for various coals. Meanwhile,combustion temperature has effect on the release process of SOx andlittle effect on the final concentration of SOx.