Since 1993, Successfully localized naval combat System has made steady development on various domestic and foreign ships. On the other hand, Engineering Control System(ECS) is dependent on foreign companies. Therefore, there is a lot of interest and research in the localization of ECS in the navy defense industry. As one of various studies, a preliminary study of domestic ECS software that can be commonly applied to naval ships is in progress. This paper propose Ecs Obts Scalable Platform(EOSPA) as the standard architecture of ECS On-Board Training System(OBTS) software by applying object-oriented programming and standardization. And this introduces EOSPA’s structure, function, and features of each component. Furthermore, high reusability and maintainability are expected in the development of ECS OBTS software applying EOSPA in various naval ships.