The utility model relates to a ring main unit grounding tool. The ring main unit grounding tool is characterized in that the ring main unit grounding tool comprises an insulation operating lever (2); one end of the insulation operating lever (2) is hinged to a grounding body head (1); one end of the insulation operating lever (2) is fixedly provided with a U-type plate (3); two opposite ends of the U-type plate (3) are both provided with installation holes; the ring main unit grounding tool also comprises a rotating shaft; the rotating shaft vertically passes through one end of the grounding body head (1); two ends of the rotating shaft are respectively installed in the abovementioned installation holes; and the rotating shaft is in clearance fit with the grounding body head (1), so that the insulation operating lever (2) and the grounding body head (1) can rotate relatively. The ring main unit grounding tool is proved on trial that after a grounding body is installed, a grounding part can be bent to be parallel to a ring main unit door, and thus grounding is ensured while the ring main unit is normally closed, thereby guaranteeing safety of electrical operators and passers-by.