Abstract: In traditional electrochemical polishing of metallic workpieces with stepped hole features, the surface polishing quality around the inner corner area is significantly worse than those in other areas, and there is a large disparity in surface quality between the surfaces of big hole and small hole after polishing. To improve these problems, a method of time-sharing and zoning electrochemical polishing was proposed, which achieves time-sharing and zoning electrochemical polishing of the inner wall of stepped holes through measures such as the design of a segmented tool cathode with convex edge and the timing regulation of output pulses. The results of multi-physics coupling simulation and experiments show that time-sharing and zoning electrochemical polishing can effectively solve the problem of disparity in surface quality between the surfaces of big hole and small hole, and the cathode with convex edge also reduces the surface roughness of the inner corner area to a certain extent. Under the given electrochemical polishing experimental conditions, by using the machining parameters of pulse peak voltage of 24 V and pulse switching frequency of 1 kHz with forward electrolyte flushing, all the inner surfaces of stepped holes can be polished to a bright and smooth state, with surface roughness around ranging from Ra 3.5 μm to 4.2 μm. Moreover, the surface roughness of the inner corner area can be reduced from around Ra 30 μm using the traditional electrochemical polishing to Ra 17 \textμm with the method of time-sharing and zoning electrochemical polishing.