Vertically grounding down-leading method for external side of composite material tower and tower thereof

The invention relates to a vertically grounding down-leading method for the internal side of a composite material tower and a tower thereof, wherein the ground wire cross arm is made from a metal material, a section of an upper metal cross arm of a grounding downlead with a certain length along a lead direction is led from the center of the ground wire cross arm, and the tail end of the upper metal cross arm vertically leads the grounding downlead down. The grounding downlead is linked to the tower by a lower metal cross arm thereof with a certain distance under a lower phase lead, and then is grounded downwards along the tower body. If the lower half tower body is a steel tube, the grounding downlead can be directly connected with the steel tube to be grounded. By the increased upper and lower metal cross arms of the grounding downlead, the tower head grounding downlead can be separated at a certain distance away from the composite material tower body. The invention enhances the line capability of power frequency pollution flashover resistance, improves the line insulating strength of lightening impulse resistance, and avoids burning a composite insulator by a power frequency follow current after the lightening flashover; furthermore, the structure is simple, and easy to implement.