Abstract: The W80/Cu-Al₂O₃ composites were prepared by powder metallurgy and infiltrating method and, the density, hardness and electrical conductivity of composite were tested. The effect of Al₂O₃ on arc erosion resistance of W80/Cu-Al₂O₃ composites was investigated. The results showed that the addition of Al₂O₃ could improve the hardness of the composites and had little effect on the density and electrical conductivity. W80/Cu and W80/Cu-Al₂O₃ composites showed little difference in arc duration and arc energy under different current conditions, but the stability of W80/Cu-Al₂O₃ composites was higher. The electric current was 30 A and the voltage 30 V, W80/Cu composite material transferred from cathode to anode in the process of the arc erosion, while W80/Cu-Al₂O₃ material transferred from the anode to cathode. With the addition of Al₂O₃, the loss of the material and the splashing decreased, and the surface of the composite became smoother after arc erosion.