The milling process is one of many machining processes for manufacturing component. The length of time in the process of milling machining is influenced by selection and design of machining parameters including cutting speed, feed rate and depth of cut. The purpose of this study to know the influence of cutting speed, feed rate and depth of cut as independent variables versus operation time at CNC milling process as dependent variables. Each independent variable consists of three level of factors; low, medium and high.Time machining process is measured from operation time simulation program, feed cut length and rapid traverse length. The results of statistically from software simulation MasterCam X Milling, then do the comparison to CNC Milling machine. The data from experiments was statistically analyzed by ANOVA and Regression methods by software Minitab 16.Results show that the greater feed rate and depth of cut shorten the operation time of machinery, whereas cutting speed is not a significant influence. The depth of cut has the highest contribution to the value of 49.56%, followed by feed rate 43% and cutting speed 0.92%. Optimal time of machining process total is 71.92 minutes, with machining parameter on the condition cutting speed is 75360 mm/minutes, the feed rate is 800 mm/minutes and depth of cut = 1 mm. Results of comparison time machining process in software Mastercam X milling with CNC Milling machine indicates there is the difference not significant with the value of 0,35%.