This research focuses on the concept and technique of Lean Production System to apply in Inventory Management and uses the technique of Process Management to estimating problems about materials supply. We solve problems by understanding current situation, analyzing processes, finding improvements. We will expect to achieve eliminating waste of Lean Production System by continuing improving. It will be very helpful for improvement of material supply processes. Additionally, proceed Kanban mechanism strengthens materials supply process. Materials are pulled by Kanban, made it arrived in time, and reduced shop floor inventory. Therefore, this research establishes one logical step to carry out Kanban mechanism. Companies can follow the rule when carry out Kanban mechanism. The result of the research displays the counting number of Kanban obviously lower the inventory after improving.