This paper introduces a study on the optimization of powder mixing discharge machining (PMEDM) of cylindrical parts made of SKD11 tool steel. In this study, many main input parameters, including the powder concentration, the powder size, the pulse on time, the pulse off time, the servo current, and the servo voltage were taken into account. Besides, the Taguchi method was used to design and analyze the experimental results. The influence of the input process parameters on the ratio of the material removal speed (MRS) to the electrode wear rate (EWR) was analyzed. Finally, the optimal input parameters to obtain the maximum ratio of MRS to EWR were proposed.