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Based on the field plot experiments of four chemical N application rates (0, 65, 130 and 195kg/hm2) and two irrigation levels (52.5 and 105 mm) applied to summer maize and winter wheat growing, the NO-3-N, NH+4-N and total nitrogen migration and accumulation in the first 450 cm depth of layered soils for each treatment were studied. The results showed that the soil texture and structure had a significant effect on soil moisture, NO-3-N and total nitrogen content and distribution in soil profile, and soil structure had a significant effect on soil NH+4-N content and distribution in soil profile. Fertilization and irrigation had different influence depth on soil NO-3-N, NH+4-N and total nitrogen, and the direct influence depth was 400, 200 and 120 cm, respectively, while the indirect influence depth was 400 cm for all. Soil NO-3-N in the treatments that irrigation level was 52.5 mm and nitrogen application rate was 195 kg/hm2, and irrigation level was 105 mm and nitrogen application rate greater than or equal to 130 kg/hm2 had obvious phenomenon of migration, and the migration depth was 250 and 400 cm, respectively. For the 0~450cm layered soils that had a loam, sandy soil and loam layer from top to bottom, the average soil NO-3-N, NH+4-N and total nitrogen content were all in the following descending order: 380~450cm loam layer, 0~120 cm loam layer, and 120~380 cm sandy soil layer. The special 380~450 cm loam layer blocked the migration of water and nitrogen. It was advised to use an irrigation level of 52.5 mm and nitrogen application rate of 65 kg/hm2 at a single time in growing summer maize and winter wheat in southeast agricultural region of Beijing.