To gain a deeper understanding of the interaction between surface water and groundwater in the water cycle of the inland basins of the Hexi region in Gansu Province, and thereby a scientific basis was provided for water resource management, the interaction and scheduling impacts of surface water and groundwater in the Taolai River Basin using long-term hydrological data combined with the WEAP-MODFLOW model were analyzed. The results indicate that the simulated groundwater extraction volume (2.461 × 10⁸ m³) closely aligns with the actual extraction volume (2.5 × 10⁸ m³), with an error of only about 1%, validating the model's effectiveness in simulating groundwater extraction. Under the projected water use scenario for 2030, without reservoir regulation, the surface water and groundwater supply volumes would be 3.840 × 10⁸ m³ and 1.982 × 10⁸ m³ respectively, revealing a certain groundwater imbalance issue. Changes in the storage capacity of the Taolai Gorge Reservoir significantly affect the surface water supply capacity, with increased storage effectively enhancing the regulation and supply capacity of surface water, thereby alleviating the burden on the groundwater system. Adopting a scheduling rule that prioritizes surface water use has a positive impact on groundwater balance, helping to mitigate pressure on the groundwater system and protect groundwater resources. Evidently, the Taolai River Basin exhibits significant variability in its hydrological cycle, and there are distinct differences in the hydrological characteristics between the Hongshui River and the Taolai River, highlighting the necessity for implementing regionalized water resource management strategies.