The invention belongs to the technical field of power grid auxiliary equipment, and relates to a self-adjusting grounding fastening structure. The structure comprises a cylindrical fixing cylinder; the interior of the fixing cylinder is hollow; a conical drill bit is arranged at the lower end of the fixing cylinder; a pull rod is arranged in the hollow part of the fixing cylinder; a plugging partis arranged at the upper end of the fixing cylinder; the pull rod comprises a connector extending out of a through hole, a hinge joint extending into the bottom of the fixing cylinder and a rod body arranged between the connector and the hinge joint and located in the fixing cylinder; the structure also comprises multiple hinge rods; the lower ends of the hinge rods are hinged between each pair ofhinge lugs on the hinge joint; the structure further comprises locking rods; the locking rods correspond to the hinge rods in position and are arranged outside the fixing cylinder in an array mode; the lower ends of the locking rods are hinged to the outer wall of the fixing cylinder; strip-shaped holes extending in the axis direction of the cylinder body are correspondingly formed in the outer wall of the fixing cylinder; and the upper ends of the hinge rods extend out of the strip-shaped holes and then are hinged to the middles of the locking rods. The structure is low in cost and convenient to construct, and can be automatically adjusted, so the tension recovery of the fastening structure is ensured.