Today, several manufacture enterprises are endeavoring constantly to receive order winners of subsidiary company product. There are tendencies to occupy competitive advantage in high position in price competition and in quality etc. But, it is not easy to keep it even if price has been cheap recently. Also, it is hard to be competitive advantage element more, because production smoothing was made much even if there is in quality. To keep or improve present competitive power, the due date rate is becoming importance. Several techniques with MRP, MRP II appeared in the 1970s by method to improve the these due date rate. These techniques have some defects to due date. Therefore, in this paper, MRP wishes to receive the due date rate that is improved more by supplementing having these defect by DBR of TOC.