The invention discloses a magnetic piece punch forming device. The magnetic piece punch forming device comprises a base and a cross beam. The cross beam is installed on the base through vertical columns. The base is provided with a female die and guide bases. Each guide base is provided with a horizontal telescopic rod. The upper portion of the cross beam is provided with an air cylinder I, and the lower portion of the cross beam is provided with a male die which right faces the female die. The lower surface of the male die and the upper surface of the female die both have ferromagnetism and are opposite in magnetic direction. The front portion of the base is vertically provided with a pair of vertical column type infrared detectors. The signal output ends of the infrared detectors are connected with the air cylinder I. When the magnetic piece punch forming device is used, a to-be-punched piece is put into the die area and then automatically guided into the groove area under the action of an electromagnet, the telescopic rods and a material stopping block, and hence punch forming cladding is completed; and the infrared detectors are arranged, the positions of hands of an operator are detected through the detectors, the working state of the male die and the working state of the horizontal telescopic rods are adjusted according to the positions, and the situation that the operator is harmed is avoided.