Abstract: To investigate the effect of N₂-water mist gas-liquid two-phase coupling on the propagation of methane explosion flames, based on a self-made mesoscale shock wave pipeline, we investigate the effect of N₂ at different injection pressures on the propagation of methane explosion flames, and visualize the flame propagation process of N₂ and water mist at different injection positions by Fluent. The results show that the performance of N₂ explosion suppression is closely related to its injection pressure. When sprayed pressure is 3.5 MPa , the flame propagation speed is greatly reduced, and the explosion begins to be suppressed. The N₂ sprayed into the pipeline ito the pipeline is influenced by the flame movement and is mostly pushed downstream to mix with methane premixed gas, diluting methane concentration. N₂ relative to water mist will first diffuse and dilute methane concentration, and then the two-phase coupling will suppress the acceleration mechanism of flame wave and pressure wave mutual promotion; the explosion suppression effect of water mist and N₂ staggered injection is better than that of parallel injection and opposite injection.