摘要：The generation of metropolis is the inevitable outcome of the development of urbanization to a certain stage. The economy and society of metropolis are in the rapid development, but this process brings great pressure to the ecological environment, especially the water resources environment at the same time. In this paper, the relationship between metropolitan economic system and water environmental system is deeply studied, and the concept of “coupling” is introduced. Based on the framework of “pressure-state-response” (PSR), 12 detailed indexes, such as total population and water consumption per ten thousand Yuan GDP, were selected to construct four subsystems. The coordination degree measurement model has been used to calculate the degree of coupling between the economic system and water environmental system. On this basis, the following conclusions are drawn through the example of Beijing city: (1) In the process of metropolitan development, the economic system and the water environmental system are interrelated and there exist a complex coupling mechanism. (2) With the adjustment of economic structure and the progress of technology, the coupling index between the metropolitan economic system and the water environmental system has been increasing, and this process shows an upward trend
