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In order to solve the problem of rational application of water and nitrogen under irrigation conditions in Northeast China, an experiment with three irrigation levels (W1:40mm, W2:60mm, W3:80mm) and three nitrogen levels (N1:180kg/hm2, N2:240kg/hm2, N3:300kg/hm2) was carried out in the field conditions with 15N isotope tracer technique. The results showed that the accumulations of ammonia nitrogen and nitrate nitrogen in the 0~100cm soil layer was increased with the increase of nitrogen application, so did the contents in the different layers. The ammonia nitrogen accumulation in 60~100cm layer and the nitrate nitrogen accumulation in 80~100cm layer were increased due to the increase of irrigation amount. The soil inorganic nitrogen residue and nitrogen surplus were increased with the increase of nitrogen application, however, the crop nitrogen absorption was decreased first and then increased. The nitrogen surplus and apparent loss was decreased first and then increased with the increase of irrigation water amount. The accumulation of fertilizer nitrogen was increased first and then decreased with the increase of nitrogen application. The proportion of accumulated fertilizer nitrogen was 2127%~3123%, and the proportion of residual fertilizer nitrogen and nitrogen loss were increased when 300kg/hm2 nitrogen was applied. As the nitrogen in maize plants, of which 6670%~7505% came from the accumulation of soil nitrogen. The accumulation of soil nitrogen in maize plants was increased first and then decreased with the increase of nitrogen application. Combined with the effects of different water and nitrogen management on inorganic nitrogen residue in maize soil, soilcrop nitrogen balance and the fate fertilizer nitrogen, the water and nitrogen combination of 60mm irrigation and 240kg/hm2 nitrogen application can ensure the full utilization of fertilizer nitrogen and reduce the residue and loss of inorganic nitrogen.