［Purposes］In order to apply SWAT model to the study of runoff process in Binan River Basin and provide theoretical basis for the rational regulation of water resources in the basin. ［Methods］Taking the Binan River Basin, a primary tributary of the Yangtze River on the left bank as an example, the SWAT model was constructed to simulate the runoff process of the basin. ［Results］1) The simulated value of monthly runoff in the validation period and the validation period is in good agreement with the measured value, with the validation period R2=0.81, Ens=0.80, |Re|=6.36%, the validation period R2=0.90, Ens=0.82, |Re|=7.85%, which shows that the SWAT model has good applicability in the Binan River basin. 2) The total annual average runoff of the basin from 2013 to 2021 is 1.79×108 m3, multi-year average runoff depth is 346.04 mm, and the runoff of each sub-basin is mainly concentrated in the flood season from June to October. The runoff in non-flood season is insufficient, and the distribution of seasonal runoff is uneven. The runoff in summer and autumn is high, while the runoff in spring and winter is low, and the overall runoff is in a downward trend. 3) the runoff depth of the basin is characterized by high in the east and west and low in the middle in space. The change rate of the runoff depth over the years shows the spatial distribution pattern of low change in the high-yield flow area and high change in the low-yield flow area. The high-yield area is mainly concentrated in Wutan, Sanhe, Guangpu Jianlong and other towns or subdistricts. The low-yield area is mainly located in Chenshi, Dingjia, Zhengxing, Laifeng, Qinggang and other towns or subdistricts, which is related to the low, middle and high gradient on both sides of the basin terrain. The distribution characteristics of large precipitation on both sides and small precipitation in the middle are consistent. 4) Under the background of future climate change, the sensitivity of runoff to precipitation change is higher than that of temperature change. When the precipitation remains unchanged, the average annual runoff depth decreases by 4.39 mm every time the temperature increases by 1 ℃. When the temperature decreased by 1 ℃, the average annual runoff depth increased by 3.37 mm. When the temperature remained unchanged, the annual runoff depth decreased by 6.73 mm for every 1% decrease in precipitation. Watershed precipitation increases by 1%, the average annual runoff depth increases by 9.13 mm, precipitation is the main factor affecting the future runoff change in Binan River basin, so it can carry out related soil and water conservation projects, optimize the land use structure, improve the utilization rate of water resources to achieve the future climate change under the scientific management of water resources in the basin. ［Conclusions］The distributed hydrological model SWAT can be used to simulate the hydrological process of the Binan River basin, and the research results can provide certain theoretical guidance for the management and control of basin water resources.