The electric knife gate valve is composed of the knife type gate valve and the electric actuator. Its opening and closing parts are gate, the movement direction of the gate is perpendicular to the direction of fluid, and the medium is cut off by the blade gate which can cut fiber materials. Electric knife gate valve makes the valve plate move up or down by power supply of electric actuator, so as to control the opening and closing of the valve. For example, equipped with sensor or digital display device, it can be controlled automatically by remote computer, and is suitable for pipes with suspended particles, fiber materials, pulp, sewage, coal slurry, ash cement mixture and other media.