摘要:In order to manage regional water resources efficiently and sustainably and promote the rational utilization of water resources, it is necessary to evaluate the water-supply benefit reasonably. On the basis of emergy theory, this paper constructs the water-supply-benefit model of economic (industry, agriculture, and the tertiary industry) and social (domestic, employment security, entertainment, scientific research) systems. Taking Xi’an from 2014 to 2020 as an example, by analyzing the energy flow of each system and the multisource water transformities, the water contribution rate, the water-supply benefit, and the unit-water-resource value in each system are calculated. For the water-supply benefits: Industry > Agriculture > Domestic > Tertiary industry > Employment Security > Entertainment > Scientific research. For the unit-water-resource values: Industry > Tertiary industry > Agriculture > Domestic > Entertainment > Employment security > Scientific research. In the economic system, the water-supply benefit and the unit-water value of industry were always the largest, followed by agriculture and the tertiary industry. However, the Pearson correlation coefficient between the water contribution rate and the output of the industrial system was only 0.52, which was less than that of other production industries, which indicates that there might be a waste of water and that industrial water conservation needs to be further strengthened. In the social system, the domestic-water-supply benefits and the water-resource value were the largest. This is because water resources, as a basic resource, always affect people’s health and quality of life.