Based on the former model in NIS and the important status of technological agencies, we divide the development process of national innovation systems into three stages which are named as Early stage, Three Subjects Mode, four Subjects Mode and then divide Four Stage Model into three periods which are Government-oriented, Universities push - enterprises pull oriented, Self-development oriented. Finally, based on the above classification, we analyze the characteristics and lessons of NIS' evolvement of China and give some suggestions since the reform. We arrived at several conclusions of tendency of the development and evolution in the futureas such as market operates, government instructs, scientific intermediary sustains, risk fund sustains and so on.