The MBSE design method using UML has not been well exhibited throughout the overall system design processes. There has been many different modeling usages of UML for system requirements proposed by many till now. The extension of UML to system modeling must demonstrate consistent representation rule throughout the overall processes. This study proposes the method of using UML with overal consistency to implement system design processes. to validate and verify the proposed UML approaches, a case study of ATACMS Block IA missile system design was implemented and the resulting products were shown. phases of the systems engineering design process, logical solution development, and physical solution development, were demonstrated