The increasing demand for agricultural products in arid and semi-arid regions of Northwest China highlights the critical challenge of water scarcity, exacerbated by shifting climatic conditions and expanding urbanization. This study aims to assess the impact of large-scale agricultural practices on water resource sustainability and explore effective strategies to enhance water efficiency in crop production. Employing the Penman-Monteith model alongside tools like CROPWAT 8.0 and ArcGIS, this research calculates the water footprint of various crops and analyzes the spatial and temporal dynamics of virtual water flows in the region. The results show that (1) in the Xinjiang Uyghur Autonomous Region and Inner Mongolia, with a water self-sufficiency rate of 100% and a low scarcity index of 0.3, substantially alleviate the water stress in Shaanxi, Gansu, and Ningxia, where self-sufficiency is about 96% and scarcity indices reach 0.8. (2) The Guanzhong area in Shaanxi, central Inner Mongolia, and southern Gansu report a high water scarcity index of 0.9, necessitating a 20% increase in crop imports and a 15% improvement in water resource management efficiency to maintain supply-demand balance. (3) Implementing water-saving technologies has reduced water usage by up to 25% in pilot areas, while the development of drought-resistant crop varieties has increased yield by 10% under the same water constraints, demonstrating vital strategies to alleviate water stress and promote sustainable agricultural development in Northwest China.