Abstract: A multi-level groundwater monitoring well,which can monitor several different aquifers in the same bore hole,plays an important role in three-dimensional description of a contamination plume.Comparied with a single-channel monitoring well,the multi-level groundwater monitoring well will save the construction cost and running cost.In the project of a typical site contamination investigation,we examined the construction of multi-level monitoring well and its sampling technology,which are introduced in the paper.