The multilayer groundwater monitoring can greatly reduce the cost of groundwater monitoring. The well pipe is a whole pipe made of HDPE material with several channels by extrusion, monitoring windows are processed at special position on each channel for corresponding groundwater monitoring layers and the rational thickness of gravel fill for sealing is designed. Based on the characteristics of multilayer groundwater monitoring well, new sealing material is developed. By the use of this groundwater monitoring technology, the demonstration projects of groundwater monitoring are successively set in Beijing, Tianjin and Gansu. By this new technology, construction area can be saved and drilling work reduced ompared with conventional technology; and compared with foreign technology, it has wider application scope with lower cost.