Abstract: An axial blower includes a cylindrical hub, a driving device for rotating the cylindrical hub through a rotational shaft, a plurality of vanes arranged to an outer peripheral surface of the cylindrical hub in a circumferential direction thereof, and a plurality of stream-line ribs each having a stream-line shape and provided at a leading edge portion of a negative pressure surface-side of each of the vanes in a range from an end portion of the leading edge portion towards a trailing edge portion of the vane. The stream-line ribs are formed integrally such that an outer surface of a cross section of each stream-line rib along a rotational direction of the axial blower forms a circular arc and a radius of a circular arc curve of the outer surface at a vane leading edge side is larger than a radius of a circular arc curve at a vane inner surface side.