Although many production scheduling systems are developed, it is difficult to introduce for medium-sized enterprises, because of high cost of initial and maintenance investment. However functions provided by it, such as available-to-promise under the restrictions of the own process, resource leveling and so on, are required by all of enterprises to make their profits. To realize a scheduling system, which can be introduced more easily for the small and medium-sized enterprises, a novel spiral-evolutional scheduling system is proposed in this paper. This system is getting started with gathering of production information in factories, and through progress monitoring a scheduling function is installed and evolved in a spiral evolutional systemizing process. In this paper, the concept of the spiral-evolutional production scheduling system is described, and the implementation of this system and the merit of introduction of it are shown.