An arc welding method of the present invention controls a short-circuit current increasing gradient (di/dt), an inflection point at which the short-circuit current increasing gradient (di/dt) changes, the current in a peak period and in a base period, and the time of the peak period in accordance with a difference between a set voltage and an output voltage. This allows the output voltage to be matched with the set voltage, and stabilizes the arc. Thereby, a stable arc welding method can be implemented, even as a method for outputting a welding current based on a welding voltage.