Abstract: In this paper the experiment results of pressure variation in well air in Lu——29 well have been introduced. The results show that the response of well water level to pressure variation in well air has relation to the period of pressure variation. The greater the period of pressure variation in well air is, the greater is the response amplitude of well water level, while the smaller is the phase lag of the response. The response quantity of well water level to pressure variation of the long period is 10.2mm in well water level variation caused by pressure variation of per hPa in well air. The phase lag produced by the response of the well water level to variation of air pressure results from permeation of water between the well and aquifer.#br#These experiment results correspond with the analysis results of the observed data and research of theoretical model.