Aiming at the mismatch between regional environmental resources and economic development, the coupling coordination degree model is used to analyze the coupling relationship between water environment and economic development system in northwest China. The results show that the overall economic development index of northwest China is lower than the comprehensive index of water environment system. The overall coordination degree of water environment and economic development is generally low in northwest China. Except Ningxia which is in a primary coupling state, the other four provinces and autonomous regions are all in different degrees of imbalance. The coupling degree of water environment and economic development in northwest China is in a medium low coupling state, and its system development has experienced three states, which are extreme maladjustment recession, serious maladjustment recession and moderate maladjustment recession. It is suggested that targeted measures should be taken to improve the coupling level of water environment and economic development with the consideration of the characteristics of regional economic development and spatial distribution of water environment, so as to maximize the comprehensive benefits of water environment and economic development.