PT Nabisco Foods is a food industry which is facing quality problem, that is product overweight. Overweight percentage existing reaches 5,44 percent meanwhile company?s maximum taret for overweight is only 3 percent. Six Sigma is a comprehensive methodology for quality improvement which is directly eliminating the main special sources of problem with DMAIC (De_firie-MeaszIre-Analyze-improve-Coniro/) approach. Six Sigma concept is aimed to increase process capability, reduce variation between outputs and adjust them with the target.Determining product O with Reguler type as the main focuss, research scope is limited in mixing, forming dan baking area. Then the actual process capability is evaluated by measuring weight and thickness parameter of base cake. For weight parameter, level sigma is 5,04 dan 99,93 percent yield. These metric value indicates that the process capability for weight parameter is quite good. On the other hand, for thickness parameter, level sigma 3,45 and 97,42 percent yield are received which points that improvement focuss on process related to thickness parameter is needed. By analyzing actual process, the root causes with highest risk level are identiiied, one of them is the leak of correlation of temperature between oven zone. The outcome of using Taguchi method is the optimum setting that are I baking time in 6 menit, suhu zone 1,2 dan 3 subsequently 500, 610 and 650 F.For the last phase of Six Sigma., author recommend utilization of control chart form for monitoring process capability continuously with thickness of base cake as the parameter.