Abstract: Geostatistics is an effective tool to study the spatial heterogeneity of elements; it is suited to research quantitatively the characters of spatial structure variation of regionalized variable. The soil nitrogen in wetland is spatial and temporal successive variant, with higher spatial heterogeneity in any scale. The variable of soil nitrogen in wetland belongs to regionalized variable with its characters of randomness and constructive property. Because 15N trace technique can trace the movement track of nitrogen, and the changes of 15N abundance caused by the movement of 15N trace matter in wetland soil have spatial heterogeneity, we can combine Geostatistics with 15N trace technique to study quantitatively soil nitrogen spatial movement in wetland. In this paper, the author tries to have relative system and integrity theory study on this question.