Abstract: 88 micro-dynamic anomaies have been found Out by systematic treatment of micro-dynamic data of water table in Tayasn well from July of 1984 to lun of 1985.Based On this, the relationship between these anomalies and seismicity in North China at the same time has been analysed.The results have shown that the microdynamic variation of waier table in Tayuan well showed anomalies before most of M > 4 earthquakes, especially it showed obvious anomalies before the seismicity in Shanxi seismic zone.So the micro-dynamic variation of water table in Tayuan well can be taken as an important way for monitorinp: the seismicity in the seismic zone.