Abstract: Mass loss process of fly ash from solid waste incineration was investigated by high temperature TG apparatus. The experiment was performed at the range of 40℃~1400℃ under heating rate of 10℃ /min and N2 atmosphere. Two main mass loss peaks were found at 800℃~1000℃ and 1000℃~1200℃, respectively. Weight loss ingredients and air pollutant were investigated by benchscale experiment. The results shows that emissions of heavy metals and air pollutant in these two temperature spans exceed National Standard, and ash melting must be operated carefully.