Modeling of fractal dimension in CNC turning of mild steel, brass and aluminium work-pieces are presented in this chapter. Spindle speed, feed rate and depth of cut are considered as the process parameters. The generated surface in CNC tuning operations are measured and processed to calculate fractal dimension. The experimental results are then analyzed with RSM. From the analysis, it is seen that the work-piece speed is the most significant factor affecting the fractal dimension for mild steel turning whereas feed rate is the significant factor for both brass and aluminium materials. It can be concluded from the analysis that for all the materials, with increase in feed rate, fractal dimension, D decreases. So, to get smoother surface, feed rate should be at low level. With increase in spindle speed, fractal dimension increases giving smoother surface for mild steel turning.