W.A. Lewis pointed out that dual economy is the basic economic nature of developing countries. From the angle of information and knowledge, all of economic system, organization and individuals are the devices of information and knowledge's production, collection, delivery and use, the key to formation of dual economy results from the difference of the capabilities and efficiencies of the production, collection, delivery and use of information and knowledge in different areas. Thus, how dual economy develops and changes completely depends on the formation and development of the related capabilities of information and knowledge in these areas.