Open architecture store management system is a developing direction of the future airborne weapon system. The motivation of the open architecture SMS is to separate weapon realization from weapon design and to realize loose coupling in weapon integration. A model driven design method for open architecture SMS is presented. In this system, a platform independent model is designed by using UML and platform specific model is designed by using AADL. Some key techniques, such as UML profile for UML model to AADL model transform method etc., are explained in detail. By taking the weapon management computer design for example, the designing flow of the system is provided. Experimental results show that the use of the developing method of the model driven architecture can provide a general solution for the design of the open architecture SMS and achieve the separation of weapon design from the weapon realization.