Abstract: For a manufacturer which bases make-to-order (MTO) as its product positioning strategy, in such competitively growing business in which customers demand a shorter and shorter delivery time, it`s important for the manufacturer to avoid unnecessary inventory of semi-finished goods but improve the flexibility of delivery and to minimize the uncertain interferences in the middle of manufacturing in order to better respond to the customers. We propose a four-step method. In the first step, employing RFM indexing method to find the most potential profit-maximizing product from the product line for export. Second step is to do a mining on sequence pattern of the bill of material (BOM) which is picked from the RFM to obtain the large frequent sequence pattern of processing. From these largest sequence patterns, in the third step, create the corresponding sequence rules and present in visualization the common parts BOM and critical parts. Fourth step is to generate a feasible as well as safe optimized quantity of production. Our proposed method can, provide as an assistance to the enterprises that they can better control the commonness of their products and processes and help them find the most appropriate parts or semi-finished goods for make-to-stock during the safe planning horizon so that they can effectively and accurately increase the inventory of these critical parts and minimize the uncertain interferences in the middle of manufacturing in order to better respond to the customers.