The effects of work¡¦s surface wavelength on the ultimate surface roughness are considered in this study. Both the experimental and theoretical studies will be done in this study. In the experimental study, the relationships between ultimate surface roughness and various operating parameters will be examined. In the theoretical study, a mathematical model relating the machining rate and various machining parameters are proposed. In the mathematical model, qualitative and quantitative properties of machining rate under various surface geometric condition are obtained by the aid of computer simulation. For the experimental study, a series of experiments will be done to investigate the effects of various factors on the ultimate surface roughness of different work¡¦s surface wavelength.The factors may include the the tool speed, the tool¡¦s surface irregularity, and the particle density of slurry. The comouter simulation indicates that the removal rate is non-linear proportional to tool speed and normal load. Besides, results also showed that the difference of removal rate between peak and valley of surface profile always decreases as the work¡¦s surface wavelength increases. The experimental study confirmed that the relationship between ultimate roughness and wavelength does exist in the specific range of work¡¦s surface wavelength . The model appears to be consistent with currently available experimental data.