The invention relates to a magnesium metal rotary kiln feed control device, and belongs to the field of magnesium metal rotary kiln automatic control. The magnesium metal rotary kiln feed control device comprises a feed control device central control room automatic control system and a feed control spot device. The feed control device central control room automatic control system includes an electrical cabinet, a screened control cable, an ethernet switch, an ethernet network and an industrial control computer, wherein the electrical cabinet is installed in a central control room, the industrial control computer is installed in a control console of the central control room, and the industrial control computer is connected with an AB programmable controller through the Ethernet switch and the Ethernet. The feed control spot device comprises a feed weighing sensor, a material bin radar material level meter and a numeric value coding analyzer. The magnesium metal rotary kiln feed control device has the advantages that automatic feeding according to actual requirements can be achieved, manual intervention in the control process is not required, control accuracy is high, control mode is simple and flexible, failure rate is low, labor intensity of workers is reduced, and the purposes of saving energy and reducing cost are achieved.