There are several blood components at the Blood Transfusion Unit to improve health services in Indonesia including Whole Blood, Packet Red Cell, Liquid Plasma, Fresh Frozen Plasma, Thrombocyte Concentrate, Kriopresipitat and Washed Erythrocyte. To provide services to consumers, this unit faces problem in the form of unbalance blood supply information and consumer demand. Consequently, management of this unit was difficult to manage the blood inventory. Aims of this study is to build an information system model using the system development life cycle approach in order to manage blood demand. Furthermore, this case adopted continuous review model to conduct the inventory policies involving safety stock, reorder point, and order quantity on each blood components. This study is able to provide benefits for Blood Transfusion Unit in order to increase service level to the customer. Further study is suggested to consider blood inventory simulation in developing several scenarios to manage blood demand.