[Objective] The soil nitrogen characteristics under different water management pattern on cold paddy were studied to provide support for selection of irrigation and fertilization pattern of environment friendly cold rice.[Methods] An in situ field experiment was conducted to investigate the effects of water and nitrogen interaction on rice yields

soil nitrogen supply and nitrogen utilization using materials Longqing rice No.2. The experiment had two water management patterns (intermittent irrigation and flood irrigation)

each pattern had four nitrogen levels(0

75

105

135 kg/hm2).[Results] Rice yield

amount of accumulated nitrogen of aerial part and nitrogen use efficiency of rice were obviously affected by water management pattern and nitrogen supply level. Under intermittent irrigation pattern

indices of effective panicles per unit area

grain yield

biological yield and grain nitrogen accumulation amount were all improved when nitrogen level increased. All these indicators performed best in nitrogen level of 105 kg/hm2. Nitrogen use efficiency was obviously affected by water and nitrogen interaction. The rice nitrogen utilization efficiency ranged from 21.4% to 59.1%. The nitrogen physiological utilization efficiency

nitrogen agronomic efficiency and nitrogen partial productivity were all decreased with the increase of nitrogen application. When nitrogen application level was 75 kg/hm2

the above three indicators of nitrogen uptake were higher than those of other treatment. Correlation analysis showed that the factors of water and fertilizer were the most important influence factors of nitrogen accumulation and nitrogen uptake efficiency.[Conclusion] Considering the contradiction between rice yield and nitrogen utilization efficiency

we should pay more attention to the pattern of intermittent irrigation plus appropriate nitrogen application.