The purpose of the present invention is to provide a rotary atomizing head that paint supplied to an inner peripheral surface is spread on the inner peripheral surface uniformly so as to improve the quality of coating and to lengthen the life of the rotary atomizing head. An inner peripheral surface 67 diametrically expanded from the center of the rotary atomizing head to a peripheral edge 61b is formed and centrifugal force generated by the rotation is applied on the paint supplied to the inner peripheral surface 67 so as to discharge the paint outside atomizingly. A step part 68 is formed at the middle portion of the inner peripheral surface 67 between paint supply holes 65d, supplying paint or solvent to the inner peripheral surface 67, and the peripheral edge 61b of the inner peripheral surface 67.