To make a manufacture plan by improving the yield of product and to improve the manufacturing cost of the product and the delivery delay of the product.

In a processing-waiting product retrieval process 101, a product whose jn(i)-th process P (i, jn(i)) of the product (i) supplied to a manufacture line is not processed and the pre-process P (i, jn(i)-1) of the process is processed is retrieved. In a next process selection process 102, at least one processing possible process which can be processed next to the process P (i, jn(i)-1) a against the retrieved product is retrieved. The total of the manufacture costs of the products (i) and the total of the delivery delay periods when the processes are processed next to the process P (i, jn(i)-1) are calculated. The most superior processing possible process is selected as the next process and a manufacture plan generation process 103 manufactures the manufacture plan for executing such processing.