The spatial distribution patterns of nitrate nitrogen (NO₃^-—N) and ammonia nitrogen (NH₄⁺—N)in typical Calamagrostis angustifolia wetland soil s of Sanjiang Plain were studied by Geo statistics method.Results showed that the variability of NO₃^-—N and NH₄⁺—N contents in different soil layers had significant difference,with the order of NO₃^-—N > NH₄⁺—N,and the reasons were mainly correlated with the differences of their physical movement characteristics.Further analysis indicated that the differences of NO₃^-—N and NH₄⁺—N contents in different soil layers or in same soil layer were much significant ( P < 0101).The distribution of NO₃^-—N and NH₄⁺—N contents in different soil layers had significant spatial structure,which accorded with different semivariogram models.The structure factors had significant effects on there spatial variability,while the effects of random factors were relatively less.Microphysiognomy characteristic was an important random factor to induce spatial heterogeneity,while water condition and soil type were two important structure factors.The maximum spatial variability of NO₃^-—N and NH₄⁺—N contents in different soil layers were observed in the direction leaning to the depression center.In addition,the studies also indicated that water condition was the main reason to induce the lower NO₃^-—N content zones to be formed in the lower hypsography of depression,while the alternation of dry and wet was the import reason to inducet he higher NH₄⁺—N content zones to be formed in the lower hypsography of depression.