The invention discloses a novel letter box structure which comprises a main box body. A supporting bottom plate is fixedly installed on the bottom end face of the main box body. A storage chamber is arranged in the middle of the main box body. An arc-shaped body is fixedly installed on the side face of the main box body. A hollow groove is formed in the position, located in the arc-shaped body, ofthe main box body. A first magnet is arranged at the bottom of the arc-shaped body. A shelf is fixed to the top of the first magnet. Air convenient to take for use serves as the medium, convenience is realized, and work is convenient; in addition, parts in the device are low in precision requirement and convenient to take for use and have the advantage of being low in manufacturing cost; moreover, the device comprises a protecting device and a speed adjusting device, the structural performance of the device can be effectively protected, the service life is high, and practicability is high.