A scientific and accurate quantification of the rainwater resource potential in the receiving area of the western route of the South-to-North Water Diversion Project (SNWDP) under climate change is of great importance for the demonstration of the scale of the subsequent SNWDP. Based on global climate model data and future land use data, coupled with the SCS-CN model and distribution fitting technology, an analysis framework of the rainwater resource potential under different socio-economic shared path (SSP) scenarios in the future was proposed and the urban receiving area of the Western Route of the SNWDP was studied. The results show that the spatial distribution of the future rainwater resource potential is larger in the south than in the north. The urbanization process has a significant impact on the rainwater resource potential in this region, especially Weinan City, Xianyang City, Yuncheng City and Dingxi City, which show significant growth in rainwater resource potential. From 2075 to 2100, the rainwater resource shows a significant growth trend and is expected to reach a maximum of 5.59×10⁹ m³. However, there is some uncertainty about the future development of rainwater resources, especially in the context of climate change, the potential of rainwater resources decreases in years and also shows an increasing trend. These results provide a scientific basis for future water resources management and regional sustainable development, and have an important reference value for the demonstration and management decision of the western route of the SNWDP.