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Hetao Irrigation District (HID) is a main grain production region in China. Soil salinization and excessive application of chemical fertilizers are main important factors that restricting the food and environmental safety in HID. Reasonable and efficient utilization of fertilizer resources on saline soil to improve crop production efficiency and reduce nonpoint source pollution of nitrogen are the effective ways to relieve the problem. Farmlands with mild (0.460dS/m) and moderate (0.951dS/m) salinization were selected, as a pure nitrogen application rate of 240kg/hm2. The same amount of nitrogen was applied to the different treatments. Five fertilization treatments (the fertilization proportion of organic fertilizer was 0, 25%, 50%, 75% and 100%, respectively) and one blank control were provided, which were designated as U1, U3O1, U1O1, U1O3, O1 and CK, respectively. The field experiment was conducted to explore the response of maize yield to organic nitrogen substituting for inorganic nitrogen fertilizer in different salinized soils, and provide scientific basis for reasonable nitrogen management. Main conclusions were as follows: the amount of nitrogen mineralization in moderate saline soil of the same treatment was significantly lower than that of mild saline soil. In mild saline soil, mineral nitrogen contents added with more inorganic fertilizer were much higher in early growth stage, while a steady increase of mineral nitrogen content was found in soil which combined application of organic and inorganic fertilizer was added during the whole growth period of maize. In moderate saline soil, there was no significant difference in soil mineral nitrogen content in different treatments at the early growth stage, the increase of applied proportion of organic fertilizer was obvious to the improvement of soil mineral nitrogen content in the later stage of crop growth. The corn yield, water and nitrogen use efficiency in moderate saline soil of the same treatment were significantly lower than those in mild saline soil, and the yield was decreased by 30.94%~63.90%（P＜0.05）, respectively. The utilization efficiency of water and nitrogen in mild saline soil was increased at first and then decreased, but in moderate saline soil it was increased gradually with the increase of proportion of organic fertilizer. The water use efficiency of mild and moderate saline soil treated with U1O1 and O1 was the highest, which was 11.84% and 27.68% (P＜0.05) higher than that of U1, respectively. These two combination also obtained the highest yield, corn N uptake, N harvest index, N recovery, N agronomy efficiency and N partial productivity. Based on the changes of corn yield, water and nitrogen use efficiency and variation of soil mineral nitrogen during growth period, the suitable organic and inorganic fertilizer management models of corn in Hetao Irrigation Area were as follows: mild saline soil should be applied with 120kg/hm2 urea+120kg/hm2 organic fertilizer, and moderate saline soil should be applied with 240kg/hm2 organic fertilizer.