Abstract: It is generally believed that the smaller the curvature radius at the tip of the lightning rod is, the stronger the electric field around the tip will be, and the better the lightning attractive efficiency will be; however, some scholars deem that the effect of the curvature radius is different by the height; other ideas show that the curvature radius brings about no effect. These inconsistent viewpoints pose a problem for design, research and application of the lightning rods. In this paper, experiments were carried out to simulate streamer and leader discharge from lightning rods with different curvature radius under the needle-plate gap. Combined with the electric field calculation in the natural lightning environment, it is analyzed whether the curvature radius affects the upward streamer discharge and upward leader discharge. The results show that there is a negligible difference of the inception time and the propagation speed of the streamer discharge under different curvature radius; when the curvature radius is less than the critical radius, there is a negligible difference of the inception time and the propagation speed of the continuous stable leader under different curvature radius; in the natural lightning environment, the change of the curvature radius only affects the electric field in the vicinity of the tip. In short, the curvature radius of the tip of the lightning rod has hardly effects on its lightning attractive efficiency.