Abstract: Normal dynamic characteristics and natural environment interference characteristics of the water temperature in Lu-32 well are summary in this paper.To explore well water temperature anomaly variation characteristics,medium earthquake within the range of 500 km from the well and far field great earthquakes are contrasted including their occurring time,space and water temperature anomalies,and it is found that there are good corresponding relations.Comprehensive analysis of existing data shows that there are additional tectonic conditions of temperature geothermal field changes of the well temperature,which can be used as one of discriminant index for precursory anomaly of near-field medium earthquakes and mediumshort-term precursory anomaly of far-field great earthquakes.