The invention relates to a grounding hanging ring installation tool for a high-voltage insulation line, and belongs to the technical field of cable or electric wire installation. The grounding hanging ring installation tool comprises a fixed seat, an operation arm and a support frame, wherein the fixed seat is of a clamp structure and is matched with the outer diameters of electric poles in an electric transmission line, and an annular sliding groove is formed in the outer side wall of the fixed seat; the operation arm is of a telescopic structure, the lower end of the operation arm is assembled with the annular sliding groove through a sliding block, and a ball articulated seat is arranged at the upper end of the operation arm; one end of the support frame is assembled with the ball articulated seat, the spatial state of the support frame is limited through an interlock pin passing through the ball articulated seat, two magnets for adsorbing grounding hanging rings are symmetrically arranged at the other end of the support frame, and the magnets are assembled with magnet sliding rails on the support frame. The grounding hanging ring installation tool solves the electrification installation problem of the grounding hanging rings in the high-voltage insulation line, so that operation safety of the electric transmission line is guaranteed, and the maintenance cost of the high-voltage insulation line is reduced.