Based on the concept of sustainable water resources management, this study defines water resources liability (WRL) as the compensation liability formed in the process of unreasonable utilization of water resources, which will lead to the damage of resources and environment. Combined with system dynamics (SD) method, a simulation model of WRL is constructed to analyze the WRL of the Yangtze River Economic Zone (YREZ) from 2021 to 2030 in three development modes, which are status quo continuation mode, economic development mode, and resource and environment-friendly mode. The results reveal that: (1) In the status quo continuation mode, the scale of WRL can be effectively controlled, and the WRL will be reduced to 11.20 billion m