Abstract:Nitrate distribution and accumulation in soil profile in Entisol in northshaanxi, Anthrosol in Guanzhong plain, Paddy soil in southshaanxi, were studied and the relationship between soil texture and nitrate leaching was described in this paper. The results indicated that due to less clay content and looseness and a fast speed of nitrification, of Entisol, nitrogen input to the soil mostly presented as nitrate, in the bottom-land of Loess Plateau, 2 months later after fertilization, the peak of the nitrate content was located in 50 cm depth, and was moved down to 100 cm depth after 4 months, 130 cm after 6 months, the peak was disappeared after near one year and the nitrate was distributed between 130 and 350 cm depth. Therefore, nitrate leaching is the main way of N losses in bottom-land in Entisol area, where the irrigation could be carried out. However, in Anthrosol, Guanzhong plain, due to a higher clay content relatively and fast speed of nitrification, and a clay layer in 80-120 cm depth was found, which block the nitrate and water leaching through, so most of the nitrate was accumulated in 0-100 cm depth, which account for 64%-74% of total N accumulated in 0-400 cm depth, and N in 200-400 cm depth was only account for 7%-13%. Even some nitrate leached deeper than 100 cm depth, which would loss by denitrification. So, there was no nitrate peak movement could be seen in the soil profile. Since soil water saturated in deep layer, in Paddy soil in Southshaanxi, it isvery difficult for water and nitrate leaching down, so nitrate was mainly accumulated in top soil layer. Nitrate leached down to deeper layer where there is an anaerobic condition, losses through denitrification.