This paper presents nomographs for evaluting the relative size of parts inventory csts yielded by the pull system and the aprts-oriented system for the multi-stage production The parts-oriented system indicates the less inventory costs under the larger vaiation of aprts demand, the larger production stages for aprts, and the higher safety stock level. The merit of pull system increases as the variation of parts demand and teh safety stock level decreases, resepctively, which have been treated as management goals of Toyota Produciton System (the typical example of pull System).