[Objective] This paper mainly analyzed the effect of water resource supply on land use structure. It might provide the bases for the policies with respect to coordinated utilization of urban land resource and water resource in the Yangtze River delta, and for decision support of water-saving society construction of the 13th Five-Year Plan, as well.[Methods] Based on the theory of structural-functionalism, having the basic functions of urban production, life and public service as core, a mathematical model was built between several pairwise factors, as productive water and productive land, living water and living land, service water and service land in the Yangtze River Delta during 2001-2014.[Results] ① There was a significant positive correlation between the supply of living water and the scale of living land. And a significant positive correlation between the supply of productive water and the scale of production land was also detected. However, the service water had no significant effect on the service land. ② The regression coefficient was 0.339 3 between living water and living land, and was 0.086 7 between productive water and productive land. ③ From the regression coefficient, the influence of water supply on living land was much greater than that on productive land. The effect of water resource supply on land use structure was positively correlated with GDP and urban scale rank. In general, a city with more GDP and larger scale might easily undergone severe feedback from water resource supply.[Conclusion] The influences of water supply on the life land and production land both existed. The influence on the public service land had not yet appeared in the Yangtze River Delta. If water resources are becoming scare, the development and utilization of urban land resources will be directly affected in large city.