The efficient quality assurance system to prevent mixed assembly in introduced in this paper, It supports JIT(Just-In-Time) based Kanban and demand pull system. A new system is designed for the synchronized production and quality assurance using barcode and production kanban card, And the performance improvement method for the stable and fast response of the proposed system is suggested in this paper also. As the result of the proposed system, we improved production status visibility and quality traceability.