The dimensions, geometrical tolerance and surface roughness of products are a great importance of all machining process. This paper has been aimed to evaluate the cutting parameters in face milling of aluminum silicon and multi walled carbon nano tubes MWCNTs. The experiments were designed using Taguchi OR L27. The volume fraction of MWCNTs, spindle speed, feed rate and depth of cut were selected as cutting parameters. The material removal rate (MRR), surface roughness (Ra), flatness error and temperature evaluated using S/N ratio and ANOVA. The results of the study showed that; the most significant factor on MRR the feed rate with contribution of 49.29% followed by depth of cut with contribution 47.05%. Depth of cut is the most significant factor that affects the surface roughness with contribution of 41.32% followed by feed rate with contribution of 36.755 % . The MWCNTs nano% is the most significant parameter that effect the flatness error with a percentage of contribution of 61.73%.