An arc welding apparatus (A1) comprising: a power supply that supplies welding power to a path including an welding wire and a base material ; a welding torch ; a wire feeder that feeds the welding wire through the welding torch at a wire feeding rate in a forward direction toward the base material and in a reverse direction away from the base material ; and a controller that controls the power supply and the wire feeder such that a plurality of unit welding steps are performed, each of the unit welding steps including a short circuit stage in which the welding wire and the base material are short-circuited and an arc stage in which an arc is generated between the welding wire and the base material , wherein, a first transition period is defined as a period from a starting point of the arc stage till the wire feeding rate (Fw) reaches a maximum forward feeding rate (Fwh) in the forward direction, and an average welding current (Iwa) is defined as an average value of welding current (Iw) during the short circuit stage and the arc stage, the controller is configured to set, within the first transition period, a current suppression first period during which welding current (Iw) is made smaller than the average welding current (Iwa), and a length of the first transition period is T0 and a length of the current suppression first period is T1, 0 < T1/T0 ≤ 0.8, wherein the controller is configured to set a current suppression second period during which the welding current (Iw) is made smaller than the average welding current (Iwa), characterized in that the current suppression second period having a starting point after the starting point of the arc stage and an end point coinciding with an end point of the arc stage, wherein a length of the current suppression second period is not less than 1% and not more than 30% of a length of the arc stage. a power supply that supplies welding power to a path including an welding wire and a base material ; a welding torch ; a wire feeder that feeds the welding wire through the welding torch at a wire feeding rate in a forward direction toward the base material and in a reverse direction away from the base material ; and a controller that controls the power supply and the wire feeder such that a plurality of unit welding steps are performed, each of the unit welding steps including a short circuit stage in which the welding wire and the base material are short-circuited and an arc stage in which an arc is generated between the welding wire and the base material , wherein, a first transition period is defined as a period from a starting point of the arc stage till the wire feeding rate (Fw) reaches a maximum forward feeding rate (Fwh) in the forward direction, and an average welding current (Iwa) is defined as an average value of welding current (Iw) during the short circuit stage and the arc stage, the controller is configured to set, within the first transition period, a current suppression first period during which welding current (Iw) is made smaller than the average welding current (Iwa), and a length of the first transition period is T0 and a length of the current suppression first period is T1, 0 < T1/T0 ≤ 0.8, wherein the controller is configured to set a current suppression second period during which the welding current (Iw) is made smaller than the average welding current (Iwa), characterized in that the current suppression second period having a starting point after the starting point of the arc stage and an end point coinciding with an end point of the arc stage, wherein a length of the current suppression second period is not less than 1% and not more than 30% of a length of the arc stage. <EOS>