In this study numerical simulation of the flash furnace copper smelting, was carried out to investigate the pollutants formation in combustion of sulfide concentrates and ancillary fuels. This simulation was done with use of Eulerian framework for continuous phase flow field and Lagrangian approach for discrete phase particles. For modeling of combustion flow and applying turbulence effects on the rate of chemical reactions used the composition of Probability Density Function (PDF) and RNG, k-ε model. Due to the thermodynamically condition of flash smelting furnace, the combustion of sulfur which is exist in Concentrate particles occurs explosively and with high radiation. Calculation The effect of radiative heat transfer was done by the discrete ordinate method (DOM). The numerical simulation results show, under combustion conditions with extra air and in partly high temperatures (>1273K) the only noteworthy sulfurous species are SO2 and in colder points SO2 is transformed to SO3. In the points which enough oxygen is not available, the concentration of SO, and S2 unburned are increased. The results also show, the maximum temperature is decreased with increase of existing sulfur in the concentrate particles and the minimum temperature is increased, because the radiation intensity is increased so the furnace temperature is more uniformly. This behavior has a significant influence on reduction thermal NOx emission.