The invention discloses an automatic metal removing mechanism of a traditional Chinese medicinal material screening machine, which comprises a conveyor belt, a rotating shaft, a motor, a pillar, a first detection mechanism, a coil, an alarm, an alarm light, a rejecting mechanism, a rejecting box, a baffle, a pole, A distance sensor, a second detection mechanism, a cylinder, a push rod, a rejecting plate, a main drive wheel, an auxiliary drive wheel, a bracket and an electric push rod. The metal automatic removal mechanism of the Chinese medicinal material screening machine of the present invention has changed the traditional detection and removal method, adopts the conveyor belt to convey the detection and removal, and adjusts the rotation speed of the conveyor belt through the motor, which can make the Chinese medicinal materials flow smoothly and improve the accuracy of the detection during the metal detection process. The rate is high, and the unqualified products are alarmed in time; the rejecting mechanism is equipped with a distance sensor and a rejecting confirmer, which can judge the position of unqualified products in Chinese herbal medicines and remove them in time, and ensure the rejecting rate and the pass rate of the product. Good economic and production benefits, suitable for popularization and use.