In response to the demand for arc erosion-resistant composite materials muzzle arc suppressor in electromagnetic rail launchers, this study prepared W/Cu and W/Cu-Al2O3 composite materials and fabricated them into discharge electrodes for the arc suppressor. By conducting material performance tests and electromagnetic launch experiments, the influence of electrode materials on electromagnetic launchers was investigated. The utilization of W/Cu and W/Cu-Al2O3 composite electrodes resulted in a significant reduction in peak muzzle voltage of the launcher, while the W/Cu-Al2O3 electrodes exhibiting superior arc erosion resistance.