| A two\|factor split\|plot field experiment with three replications was conducted in 2021 and 2022 with Ningchun 4 as the test material. The primary treatments involved different irrigation quotas: conventional irrigation (WC) with 400 mm, W1 with a 20% water saving (320 mm), and W2 with a 40% water saving (240 mm). Secondary treatments included nitrogen application rates: NC (270 kg·hm-2), NJ (a 25% reduction in nitrogen fertilizer, 202.5 kg·hm-2), and N0 (no nitrogen application). The study aimed to investigate the effects of reduced nitrogen application and water\|saving practices on soil water distribution, crop yield, and water use efficiency in spring wheat. The findings are intended to provide a theoretical basis for efficient water use under reduced nitrogen fertilizer in the Ningxia Yellow River irrigation area. The results indicated that reducing nitrogen by 25% and saving 20% of water increased water uptake by spring wheat in the 20~40 cm soil layer. Most changes in soil water content occurred above 60 cm, which limited the downward movement of water. At the same time, the highest yield of spring wheat was achieved with the treatment 25% N reduction and 20% water saving, 8 092 kg·hm-2 and 5 516 kg·hm-2 in 2021 and 2022, increasing by 7.01% and 13.36% as compared with the conventional irrigation quota and N application. Meanwhile, the number of grains on the spike and the thousand grain quality of spring wheat were significantly raised with the treatment 25% N reduction and 20% water saving. Under the same N application, the total water consumption was significantly different between irrigation quota treatments and tended to increase with the increase of irrigation quota, and the water consumption of spring wheat under 25% N reduction and 20% water saving treatment decreased by 14.07% and 18.37% compared with that of conventional irrigation, respectively in 2021 and 2022. The water use efficiency of spring wheat with 20% water saving under N reduction were up to 1.62 kg·m-3 and 1.43 kg·m-3, which were 21.80% and 31.19% higher than that of the conventional irrigation treatment. In conclusion, during a dry or extremely dry year with only 67.5 mm or 34.5 mm of rainfall during the spring wheat growth period, a 25% reduction in nitrogen (202.5 kg·hm-2) and a 20% reduction in water usage (320 mm) represent an optimal irrigation and nitrogen management strategy. This approach ensures high yield and efficient water use for spring wheat in the Yellow River irrigation area. |