By newly-developed computer model[1, 2] of the distribution behaviors of minor elements As, Sb, Bi and accessory elements Pb, Zn in copper flash smelting, copper flash smelting process of Guixi Smelter was simulated. Results showed that the predictions by the computer model were in agreement with the known commercial data from Guixi Smelter. Using Nagamorips physical suspension index equation[3], the apparent percentages of Cu and S in the slag were calculated, and the main form of mechanically entrained copper particles in the slag was determined to be sulfide. Furthermore, the effects of smelting temperature upon the fractional pressures, activity coefficients of As, Sb, Bi, Pb, Zn, etc. and their distributions in matte, slag and gaseous phase were analyzed. According to the simulations, when smelting temperature rises, the volatilizations of As, Sb, Bi, Pb and Zn in gaseous phase increase, while their distributions in matte decrease. The increase of smelting temperature is helpful to improve the total elimination rate of above-mentioned elements in gaseous and slag phases.