Under the background of global climate change and the prominent problems of big cities in developing countries, countries pay more and more attention to environmental issues and actively explore the way of sustainable urban development in the future. Building ecological cities has become a global consensus after 2000, a number of outstanding eco-city practice cases have emerged all over the world, which have accumulated experience for us to explore the path of eco-city coustruction. Based on the practice of global eco-city construction after 2000 , this paper sums up the construction experience of European and American countries by comparing their eco-construction characteristics, key areas, construction methods and guarantee mechanisms, and draws lessons from the application of their material circulation concept in eco-city construction. On this basis, in view of the confusion encountered in the construction of ecological cities in China, this paper puts forward the construction ways of ecological new cities and green transformation of old cities in line with China's national conditions.