The present disclosure relates to a deburring device and method for a metal workpiece. The deburring device for the metal workpiece includes a power source, an insulating tube, a tank and an electrolyte contained in the tank. A first end of the insulating tube communicates with the electrolyte, and a second end thereof projects into a hole with burrs to be removed in the workpiece. A first pole of the power source is conductive with the workpiece, and a second pole thereof is configured to be conductive with the electrolyte. A gas layer can be formed when the power source is turned on and the electrolyte is introduced into the burr location in the hole through the insulating tube, and the gas layer is broken down under the action of a voltage to remove the burrs.