Based on a comprehensive analysis, this research reviews and evaluates the existing social security system covering the urban and rural inhabitants. The study analyses theoretical constraints, basic ideas, targets, and fundamental framework in light of experiences in other countries. In view of the characteristics and differences between the urban and rural developments, it dwell specifically on the basic endowment insurance system Covering the City and Countryside Inhabitants, basic medical insurance system, the minimum insurance and help system, and basic welfare system. Accordingly, it analyzes the possibility and feasibility to raise money for the social security System Covering the City and Countryside Inhabitants, capacity to governance, institutions, their interfaces, and coordination and policy linkages. In the end, in view of the medium and long term goal of economic development, it puts forward such proposals as strategic steps so as to provide theoretical guidance and recommendations for the government.