Abstract: Al0.5FeCoCrNi high-entropy alloy was prepared by arc-melting and then was heat-treated at 800, 1 000 ℃. The effects of heat treatment and erosion angle, erosion rate and erosion time in liquid-solid two-phases folw on erosion wear resistance of the high-entropy alloy were studied, and then were compared with 00Cr13Ni5Mo stainless steel. The results show that the mass loss rate of the two materials were largest when the erosion angle was 45°, and they exhibited the erosion wear characteristics of ductile materials. Mass loss rate of the two materials all increased dramatically with the increase of erosion time and erosion rate. Heat treatment could increase the hardness and erosion wear resistance of the high-entropy alloy, and the hardness and erosion wear resistance heat-treated at 800 ℃ were relatively good. The erosion wear resistance of the high-entropy alloy was better than the stainless steel. The erosion wear mechanism of the high-entropy alloy was dominated by cutting, plough cut and plastic deformation, and that of the stainless steel was dominated by cutting, extrusion deformation and peeling off.