A blower fan includes a plurality of blades radially extending from a boss provided at a rotary center and spaced apart from each other in the rotational direction, and a ring portion connecting outer peripheral ends of the blades in a ring shape. A radially outer end part at an end on an air-flow upstream side of the ring portion is positioned outward in a radial direction of a rotary shaft in the blower fan, as toward the air-flow upstream side. Thus, the blower can prevent the backflow air from being swirled, thereby reducing noise.