The problem of establishing weapon system safety especially during the development process has been one of the very important fields related with public safety in advanced countries such as USA, UK and so on. These countries have launched strong policies on system safety to reduce the chance of accidents. However, the Republic of Korea (ROK) has limited experiences and application of the system safety on domestically produced weapon systems. Therefore, it is imperative that the government starts a comprehensive and systematic policy on system safety to reduce the occurrence of potential accidents during the development of weapon systems. In this paper, we analyze system-level activities needed through the life-cycle of the weapon systems and provide a suggestion for application of the system safety.