Abstract: Water resources are fundamental natural resources and strategic economic resources,as well as controlling element for ecological environment improvement.Water amount per capita in China is about 2 200 m³ on average,which is less than 1/3 of world average,meanwhile,the spatial and temporal distribution of water resources is quite uneven.Water resources regime in China is undergoing a new changing due to double stresses from global climate change and large-scale economic development.Therefore,the concept of water resources management needs to be changed from water supply to water demand.The definition and connotation of water demand management are discussed from different aspects for the purpose of whole profound understanding of water demand management.Water demand management is a sequential system engineering to balance water supply and demand between all water consumers including human being through adopting administrative economic measures and law,to improve water utilization efficiency through limiting irrational water requirement.Briefly,the idea of water demand management is to allocate water based on water supply rather than water requirement,the final target is to realize the harmony of human and water resources,and achieve sustainable utilization of water resources.