The study aims to master the natural precipitation patterns, water consumption and demand patterns of major crops, regional crop layout, and farmland water resource regulation in the Xing'an League region, which are important tasks for agricultural production and research. This study utilized meteorological data from the Zhalaite Banner National Science and Technology Demonstration Park in Xing'an League, Inner Mongolia, and used the FAO Penman Monteith formula and water balance method to investigate the water consumption patterns of major crops such as semi-arid corn, peanuts, and foxtail millet in Xing'an League, Inner Mongolia. Research indicated that among several major crops, soybean had the highest field water consumption and significant water deficit throughout their entire growth period, followed by corn. Peanuts and foxtail millet consumed less water in the field, resulting in relatively low water deficit. From the perspective of water use efficiency, the priority planting order of crops in the region should be corn > millet > peanut > soybean. From the perspective of water economy benefits, the order of priority crops planted in the region should be peanut > corn > foxtail millet > soybean; the priority crops for irrigation were peanut > foxtail millet > corn > soybean. Soybean planting should adopt the intercropping mode of corn and soybean, which had relatively high water use efficiency and water economic benefits. This study provides suggestions and recommendations for effectively adjusting regional crop layout and regulating agricultural water resources.