Abstract: In the rare-earth electrolysis process, the flow state of the electrolyte significantly affects the electrolysis efficiency. Once the electrolysis cell is energized, bubbles generated at the anode induce the molten electrolyte in motion. As a result, the bubble escape rate from the anode wall surface, which varies with different electrode spacing, plays a crucial role in the electrolytic efficiency. Therefore, this study focused on an 8 kA rare-earth electrolysis cell from a non-ferrous enterprise as the research object to explore the relationship between the bubble flow field and the electrolytic efficiency. Considering that the conventional electrode spacing for an 8 kA cell typically ranges between 80 and 90 mm, five specific cases with electrode spacings (75, 80, 85, 90, and 95 mm) were selected for flow field simulation and analysis to ensure scientific rigor.The experimental results showed that the eddy current in the flow field reached a relatively stable state at about 25 s of the melt redox reaction, and changes in electrode spacing had a significant impact on the maximum flow velocity and the area of eddy current between the anode and cathode electrodes. Specifically, the stable maximum flow velocity of the electrolyte peaked when the electrode spacing was approximately 85 mm. Although the area of the eddy current between the electrodes reached its maximum at an electrode spacing of 95 mm, the small eddy current at the bottom of the cell was segmented by the inter-electrode vortices, which hindered the collection of rare earth metals. The simulation results showed that for an 8 kA Pr-Nd system electrolysis cell, an electrode spacing of approximately 85 mm optimized the flow in the lower part of the melt, thereby maximizing the precipitation and collection efficiency of metallic rare earth.