China railway has been playing an important role in the economical development and having been confronted with the requirement of higher speed, higher capacity of transport, higher degree of safety and higher quality of services. With the development of artificial intelligence, communication, computer and its related technologies, it becomes feasible to rebuild traditional railway with such advanced technologies in order to resolve the problems above mentioned. China railway had started informatics-based construction on train planning, dispatching, interlocking and other special fields from early 1980 successively. The conditions. are ready for the transformation of railway transportation system to the railway intelligent transportation system (RITS). Establishment of system architecture is the first step to develop China national RITS. This paper presents the current states for the research and development of information and intelligence technologies in China at first. On the basis of discussion about the definitions and goals of China national RITS, the develop principle and the system architecture which includes service architecture, logical architecture and physical architecture. for China national RITS are discussed at the end.