The study area is located in the suburbs of Xinhe County Town in the Ogan River watershed, Xinjiang. The soil texture is
dominated by the homogeneous loam, the light sandy soil and clay occupy 66.5% and 33.5% respectively, the content of organic matter in soils varies in a range of 1.14～1.32%, and the content of calcium carbonate is about 20%. The growing area of vegetables is about 400 hm2 in Xinhe County, and the annual yield of vegetables is 6 660 t. In this paper, the soil
nitrate-nitrogen leaching in the vegetable plots in the suburbs of Xinhe County Town is investigated. The results show that nitrate-nitrogen is seriously accumulated in the soil layer of 0～2.8 m in depth due to the excessive application of nitrogenous fertilizer and irrigation. The average accumulation of nitrogen in the soil layer of 1 m in thickness is 252 kg/hm2, which is about equal to the nitrogen requirement of vegetable production in one season. The average accumulation of nitrogen in the soil layer of 0～2.8 m in thickness is as high as 588.4 kg/hm2, which has threatened the shallow groundwater. The accumulation of nitrate-nitrogen in the soil layer of 0～2.8 m in the vegetable plots and the applied quantity of nitrogenous fertilizer are in a significant positive correlation, i.e., Y=0.353x+288.11, R=0.8986. Both the absolute and relative accumulations of nitrate-nitrogen are high in the soil layer deeper than 1 m in the vegetable plots where vegetables are planted for many years.