The utility model discloses a protective earthing device, including a pipe body, body upper portion sets up the end of cross sectional shape for T shape, the end upper end sets up the screw thread post, threaded connection nut on the screw thread post, the nut is used for being in the effective connection of earth conductor on the screw thread post, body inside sets up leading electrical pillar, the body with it has carbon dust polymer layer to fill between the leading electrical pillar. The utility model discloses ground resistance can be reduced moreover to not only can be firm contact with the earth soil to effectively play the effect of ground protection.