Early warning device for edge protection

The utility model discloses an early warning device for edge protection, and relates to the technical field of building construction. The early warning device for edge protection comprises a main warning board, the top of the main warning board is fixedly connected with a shell, the lower surface of the main warning board is fixedly connected with a placement plate, a moving device is movably installed in the shell, and the front face of the shell is fixedly connected with a solar panel. The moving device comprises a sliding block, a connecting plate, a threaded bearing, a short column, a threaded rod, a supporting rod and a motor, the motor drives the threaded rod to rotate, the threaded bearing is matched with the threaded rod to drive the connecting plate to move, the supporting rod is pushed out of the shell, and the short column is rotated to drive the supporting rod; when the extension plate is extended to meet the edge with the width larger than that of one early warning device but smaller than that of