Abstract: In order to solve the influence of gases with multiple different natures on the methane burning process,using the CHEMKIN-PRO software,a USC Mech 2. 0 dynamic model was built to further study the combustion process of gas mixture consisting of different components’ C2 H4 / CO2 . Then the change tendency of laminar burning velocity and H and O free radical’s volume fraction were simulated and analyzed under different components. The program SEN- KIN was used to analyze the sensitivity. The calculated results showed that the laminar burning velocities of methane decreased with the increase of the volume fraction of CO2 ,and they decreased 13 cm / s,149 cm / s respectively under different conditions of φ1. 25. H and O volume fractions reduced and their synergistic effect was to inhibit the gas burning. The laminar burning velocities of methane increased slightly with the increase of the volume fraction of C2 H4 ,and they increased 3 cm / s and 46 cm / s respectively under different conditions of φ1. 4. H and O free radical’s volume fractions increased correspondently and their synergistic effect was to promote the gas burning. With the equivalence ratio increased,the reduction about the sensitivity coefficient of key step reaction on the promotion of CH4 generated was larger under the condition of φ≤1,so it inhibited gas burning.