[Objective] The spatial and temporal distribution characteristics and influencing factors of the water supply in Dalian City of Liaoning Province were studied in order to provide visual evaluation results and a basis for the development and protection of water resources.[Methods] Based on the InVEST model, the characteristics of rainfall, air temperature, potential evapotranspiration, actual evapotranspiration, and land use in Dalian City from 1980 to 2015 were investigated. Quantitative estimation of spatial and temporal distribution characteristics and causes of water supply in Dalian City from 1980 to 2015 were also analyzed.[Results] ① From 1980 to 2015, the average annual precipitation and potential evapotranspiration of Dalian City did not decrease significantly, the average annual temperature and drying coefficient increased significantly, and the annual actual evapotranspiration decreased significantly. ② The area of cultivated land and woodland decreased, the area of urban construction land transferring from increased, and the area of other land types had less change. ③ The average water supply was 226.36 mm and the total water production was 2.70×10⁹ m³. It showed a trend of decreasing form the northeast to the southwest. The annual water production in Zhuanghe City was the largest, reaching 1.10×10⁹ m³.[Conclusion] The change of water supply was resulted from both climate change and land use. Climate change was the main driving force for water supply change, and land use change had some slight effects on the increase of water supply.