PURPOSE: To provide an electric processing method wherein stable processing is carried out without accompanying the short-circuit and breaking down by melting of a wire electrode by comparing detection signal voltages at a processing gap with an arithmetic mean voltage, and controlling amplitude values of the wire electrode according to the results of comparison.

CONSTITUTION: A pulse current is passed between a processing gap between an electrode 1 and on object 4 to be processed so as to carry out discharge processing. At the time, an arithmetic mean voltage of the processing gap is operated by inputting processing pulses, etc of a power source 9 to a logic operation circuit 16, and then inputting to the said judging circuit 15. Also, signal voltages from the processing gap detected at a detection circuit 17 are inputted to the said judging circuit 15 where the signal voltages detected are compared with the said arithmetic mean voltage as a standard value. Wire vibration is controlled according to the results of comparison, being controlled to a small amplitude of 1W2μ for normal processing, and a large one of 5W8μ for abnormal conditions. Thus, stable processing is carried out without accompanying the breaking down of the wire electrode 1 by melting due to short circuit.