The technology of incinerator fly ash as the main material and the core carbonaceous reducing agent, and the necessary absorption of chlorine and catalyst made of composite pellets, Into the garbage incineration furnace temperature reduction decomposition of dioxin, heavy metal forming glassy slag. The fly ash harmless treatment, fly ash in the incineration plant in their complete closed circulation waste disposal to achieve, Provides the optimum technical route for the treatment of MSW fly ash.