In the computer numerical control (CNC) pad polishing technology, the working function of the pad is an essential function during fabricating the workpiece. Based on the research results of the known mathematic modeling and working characteristics of a round pad, the working function and its characteristic curve of an elliptical pad in conditions of planet motion and translation are discussed, and the working parameters after optimization are analyzed and obtained by simulation. The results show that the working characteristic curve of the pentagon-shaped pad has the central peak in the conditions of both commonly-used motions, which similar to the Gauss distribution, and the pad has good material removal ability.