Abstract: By changing the simulation conditions of municipal solid waste incineration experiment (nickel catalyst, water), analysing the reaction temperature, incineration exhaust gas flow, concentration of exhaust gas composition, the dioxin concentrations, the toxicity of dioxin equivalent of absorbing liquid, and the change of the absorption liquid organic matter concentration, the effect of different combustion conditions on dioxins from simulated municipal solid waste incineration was explored. The results showed that the addition of nickel catalyst and water could promote the conversion of macromolecule organic matter to small molecule organic matter during the incineration process, and effectively inhibited the precursor synthesis of dioxins, while the suppression ratio of dioxins were 80.7% and the total equivalent toxicity of dioxins were decreased by 98%.