The screw bolt dismantling tool includes a shaft. The shaft has a handle and a working portion at two opposite ends thereof The working portion includes a seat and at least one abutting piece. The seat has a magnet on a central portion of a face of the seat opposite to the handle. The abutting piece is located at a periphery of the face of the seat opposite to the handle and extends toward a direction opposite to the handle. The abutting piece is non-magnetic.