The electric permanent-magnetic chuck is the new type magnetic chuck making use of electric pulse for “switching On and switching Off” magnetic force. After holding workpiece with magnetic force, this chuck will keep the attraction indefinitely. The time need for “On/Off” is less than 1 second. The energy consumption of electric pulse is very small, so the chuck will not be heated and distorted. The electric permanent-magnetic chuck is without mechanical moving components, so it is with stable & hard structure and high precision. Switching on and off with electric pulse in convenient automatic control. The electric permanent-magnetic chuck can be widely used as holding component of various kinds of plain surface grinder and electromachinging machine tools. The high power electric permanent-magnetic chuck can also be used for holding workpiece for milling machine , drill press, planning machine and boring lathe. Furthermore, it is also adopted in the machining center and FMS system as attached fixture device.