The invention discloses an axial flow blower, which comprises a net cover, an impeller, a guide vane, an inner cylinder, an outer cylinder, a motor and a shaft sleeve. The net cover is fixed on the outer cylinder, is of a concentric structure and is formed by weaving iron wires; the impeller comprises a wheel hub and vanes, and the vanes are airfoil vanes which are designed through a constant circulation isolated airfoil method; a fin-shaped vortex breaking structure is arranged on a part, close to the root, of the suction surface of each vane; the top parts of the vanes are machined into an airfoil groove structure; and a labyrinth seal structure is formed in a gap between the wheel hub of the impeller and the inner cylinder. The shark fin-like vortex breaking plate is additionally arranged on the part, close to the root, of the suction surface of each vane of the impeller of the axial flow blower, the airfoil groove is formed in the top of each vane of the axial flow blower, and the labyrinth seal structure is formed in the gap between the wheel hub of the impeller and the inner cylinder, and different positions of the axial flower blower are improved, so that the efficiency of the axial flow blower is relatively high, the noise is relatively low, and the energy conservation and environment protection are achieved preferably.