PURPOSE: To obtain an effective current control device for resistance welding machine with increase response of welding current control, by constituting so that the error of the current-time product actually flowing may be as small as possible with respect to the setting of the current-time product of the resistance welding.

CONSTITUTION: Contacts 18, 6 are closed by a weld start signal, and a reference input proportional to the set current is applied to an adding part 3. Passing the welding current from 0 or a specified level, the welding current is settled approximately at the set current value after matching time of several cycles. After energizing for a specified number of cycles, the contacts 18, 6 are opened by the output of a cycle control part 13 to set the welding current to 0, and the output of an amplifying part 4 is kept at a voltage just before opening of the contact 18. Then, closing the contacts 18, 6, power is supplied at the same firing angle as the firing angle of the final energization cycle of the previous welding. Afterwards, the firing angle is automatically controlled so that the current may be close to the set current value depending on the load impedance. Thereafter, the firing angle of initial energization at every welding point is made approximately equal to the final firing angle of the previous welding.