The utility model discloses a joint style annular earthing device, it includes fixed plate and wiring board, be provided with the arc hole on the fixed plate, and the segmentation of arc hole sets up just follows the setting of different circumference diameters, the middle part of fixed plate is provided with three connecting hole, and is three the circumference equipartition is followed to the connecting hole, the both ends of wiring board set up the one bolt hole respectively, the inner bolt hole of fixed plate with arc hole on the fixed plate is corresponding and the two is together fixed through connecting bolt. Fixed plate and wiring board are made by the copper plate, the wiring board is rectangular shape, the fixed plate is circular. The utility model discloses the same type earth connection of the different equipment that can set up the annular inserts the same ground point of uniting to reach the mesh that reduces construction man -hour and distinct all kinds of grounding types.