This paper studies the efficiency and influencing factors of interprovincial water use in China

and provides reference for the construction of a water-saving society. First

an improved data envelopment model is used to calculate water use efficiency in different regions from 2015 to 2020. Then

compared with the results of ordinary least square regression

quantile regression is used to explore the influence of various factors on water use efficiency at different grades. The results show the average water use efficiency in China fluctuated around 0.45

showing an inverted "U" shaped trend. Regional water use efficiency is eastern

central and western in descending order. Water use efficiency is impacted significantly by natural factors

economic development level

sustainable use level

scientific and technological progress

human literacy

and enterprise cost. Among them

the impact of water endowment is significant on the areas with low water efficiency

while it is not significant on the areas with medium or high efficiency

which is different from the "resource curse" hypothesis. Thus

there is still much room for improvement in China's water use efficiency

especially in the low efficiency areas.