At present, urban space has been developed under the support of scientific rationality, technological rationality and empirical rationality, it shows two characteristics in the process: Firstly, In the process of development and Self-renewal, urban space adapts to the function demand of culture, system, spirit and material in different periods. Also subject to the corresponding values and cultural concepts, the development of urban space shows the pursuit of ecological, social and economic harmony and balance of the self-discipline characteristics. The investigation tries to discuss the cultural-ecological mechanism of urban space sustainable development, as well as its value, significance and path through the case of Xi ' an which was a typical city in the mainland of China.