The invention provides an anti-corona ball used for a squirrel-cage rigid jumper device, belonging to the field of overhead installation of electric wires or cables. The anti-corona ball provided by the invention is arranged on the cable clamp of the spacing rod at the end part of the squirrel-cage rigid jumper device in a 750KV transmission line, a curvature radius at the contact spot between the end part of the spacing rod and a lead wire can be indirectly increased, so the anti-corona ball has a regular round surface in appearance, accordingly, the distribution of electric-field strength on the surface of the end part of the spacing rod can be effectively improved, the corona discharge phenomenon of the end part can be restrained, the corona noise and the corona loss in a transmission line can be reduced as well as energy conservation and noised reduction can be realized. The anti-corona ball comprises hemispherical shells and a bolt, wherein the two hemispherical shells are fastened together by using the embedded bolt. The anti-corona ball provided by the invention has a small volume and light weight, is convenient to install, does not need to disassemble other gold fittings in the original line during installing and is easy to operate and maintain.