Abstract: In order to demonstrate the optimality of the hybrid push/pull control strategy,a softwarepackage for simulation of production/inventory control strategles is developed．It uses the structure model todescribe the relation of different processing and assembling stages,and bses the different siniulation equationsto describe the material flows of different stages controlled by different strategies, The simulation resultshave proven that the recommended hybrld push/pull strategy is still optinial for general mass manufacturing systems．