Based on meteorological data, remote sensing data, and population density statistics from 2000 to 2023 in the Yanhe River Basin, the ecological water demand and domestic water demand in the basin were calculated. It also analyzed the spatiotemporal evolution characteristics of the basin's water demands and explores the relationship between vegetation ecological water supply and demand. Besides, the ecological water demand and domestic water demand in the basin exhibited a significant upward trend, with an annual growth rate of 73 million. The growth rate of vegetation ecological water demand exhibits a spatial distribution pattern with lower values in the south and higher values in the north, primarily driven by precipitation and the increase in grassland vegetation cover due to the policy of converting farmland to forest. However, due to the uneven spatiotemporal distribution of precipitation and the limited water storage capacity of the soil have exacerbated ecological water shortages as ecological water demand increased. This issue was particularly severe in the central part of the basin. Moreover, during the vegetation growing period (April to October), ecological water shortages displayed a seasonal pattern of initial reduction followed by an increase. Additionally, the increasing trend was also reflected in the domestic water requirement, primarily driven by rising population density and livestock breeding, with an average annual growth rate of 84,100 m³. In summary, although ecological restoration has significantly improved vegetation coverage in the Yanhe River Basin, the limited precipitation exacerbates the supply-demand conflict of water resources due to ecological restoration. Simultaneously, socio-economic development has led to a gradual increase in domestic water demand, further compounding this contradiction. These findings provide scientific evidence for optimizing watershed water resource management and ecological restoration policies in the Yanhe River Basin.