Original satellite management relies heavily on ground control while remains the problem of low time efficiency and high labor cost, which cannot satisfy the growing demand of satellite autonomous management. As one of the key technologies, multi-satellite coordination autonomous mission planning can achieve real-time monitoring, quick responding and independent decision making, which will be more widely applied in satellite autonomous management. Furthermore, it brings great challenge to the system architecture due to the sequential complexity and frequent interaction of multi-satellites and loads. Based on the above considerations, we propose the hierarchical system architecture design of multi-satellite coordination autonomous mission planning, which takes the top-down method and decomposes the system into inter-satellite link communication layer, constellation mission planning layer and inner-satellite mission management layer. Inter-satellite link communication layer focuses on the link establishment and instant messaging among networking satellites as well as ground management system. Constellation mission planning layer is in charge of target tracking state maintenance and multi-satellite observation task arrangement. Additionally, executive state management of the local satellite is achieved by inner-satellite mission management layer. Adopting hierarchical data structure and object oriented design technique, we can enhance the performance of planning system as well as improve the maintainability and extendability. The validity and feasibility of the system architecture are verified by the visualization simulation system, which promotes the development of multi-satellite coordination autonomous mission planning in target observation and other fields.