Abstract: Satellite Keeping Operation (SKO) system first applied to chinese mission is an comprehensive automatic system which accomplishes satellite operating management, autonomous control, information transmission and ground-to-satellite loop operation. SKO is the flexible satellite-borne system which cooperates and schedules contact between various satellite components with use on-board network to perform dynamic stream tasks including information stream, action stream and energy stream. SKO has several innovations as follows: multilevel control, embedded management executive unit, field network technology, hardware/software encapsulation technology, utilization of the commercial RTOS, compatible package telemetry, compound tele-command and tele-operation technology, data multi-path and reconstruction technology, test-bed technology, radiation shielding technology, etc. Autonomous capability and intelligence of the satellite are enhanced and risk of the mission is decreased by the application of SKO to SJ-5 mission. Also top-level reliability and efficiency of mission operation are improved.