This Article presented a numerical investigation for the optimal design of the accelerator disk of a two-stage piston pusher centrifuge, including the disk structure and the blade geometry. With six blades added, a novel accelerator disk was designed, and the effects of these blades on the centrifuge performance were analyzed. The calculated results showed that such new disk design could improve the mass flow rate and the transient velocity of the particles. Therefore, it indicated that the flow field was mostly dominated by blades. Besides, the new disk was tested by an industrial experiment. However, unfortunately, due to that the edges of blades were fractured during the industrial experiment, the geometric outline of the blades was further investigated. The force analysis results showed that the height and length of the blades had a major effect on the blades stresses. Thus, three ways including reducing height, shortening length, and cutting 45 degrees angle were adopted to decrease the blades stress. Finally, according to the calculated results, an optimized geometric outline of the blades was obtained, and a disk with new design of blades was experimentally tested, which validated the design and optimization process by its good performance.