Due to the spherical shape, the spherical electrode has different etching depths in ICP(Inductively Coupled Plasma) etching, and the resonator following the stopping layer is often damaged in the thin place of the electrode before the ICP etching front reaches the stopping layer in the thick place of the electrode. Therefore, this paper proposes a novel method to fabricate 3D silicon spherical electrodes. On the basis of the inhenrent lag effect of ICP etching, a V-shaped mask with an open window width gradually shrinked from 60 μm to 10 μm was used to modulate the etching speeds of the electrode and the etching speed was tuned to be a normalized speed nearly 2.3 μm/min in all places of the electrode. Then, a silicon step structure was used to simulate the 3D spherical profile of the electrode and to ensure the silicon depth of the last step to be about 150 μm, by which the etching front across the spherical electrode could be made to reach the stopping layer almost simultaneously. With the step-shaped silicon dioxide mask, the normalized ICP etching depth of the spherical electrode was tuned to be approximately the same and the spherical electrodes were fabricated successfully by one ICP etching process. It concludes that the silicon spherical electrode with functional output for MEMS hemisphere gyros can be fabricated successfully, and the maximum radius of the sphere is 500 μm.