The invention discloses an impulse current generating device. The device comprises a charging circuit and a discharging circuit, wherein both the charging circuit and the discharging circuit are connected with an acquisition element and then controlled by an industrial personal computer; the charging circuit comprises a charger, a rectifying device and a supercapacitor which are sequentially connected with one another; the discharging circuit comprises the supercapacitor, a thyristor, a current divider and a to-be-tested conductive connecting piece which are sequentially connected with one another; and the charging circuit charges the supercapacitor, and the supercapacitor is served as discharging current sources to generate non-oscillating kilo-ampere level impulse current. The supercapacitor is served as the discharging current sources, and when the supercapacitor which is fully charged discharges to the resistor of a to-be-tested circuit, kilo-ampere level impulse current is generated and can be maintained for a longer time through adjusting all parameters, so that the requirements of measuring the resistor of a high-voltage melting furnace conductive connecting piece circuit are satisfied.