Abstract: The mutual influence of the material addition process on the temperature and electrolytic current of rare earth metal electrolyzer was studied. A rare earth molten salt electrolytic processing system was established. The powder feeder for rare earth metal high temperature electrolysis is developed based on hydraulic lifting device, screw feeding device and servo mobile device. And its methods for feeding materials were also studied. S7-200 PLC control system and servo control system were used to develop an automatic feeding control system with flexible adjusting parameters. The development of powder feeder and control system has achieved the automatic feeding of rare earth metal electrolysis instead of hand-feeding. It has improved the uniformity and accuracy of feeding. It has also improved the working conditions for workers, reduced labor intensity, improved the quality and production efficiency of rare earth metals and lowered production costs.