Abstract: In this paper, the date of Tianchuan well water level is systematic analysed.The result indicates that the water level of Tianchuan well shows 5 times clear anomalies since the beginning of observation, the anomalous features are mainly decline type, the anomalies have the course of decline and lowest value and rise.The anomalous duration is long.Middle earthquakes occurred in each anomalous course.The anomalous determination criterion is water level lowering over 30cm.At the same time, some exiting problems in the observation of Tianchuan well water level are find out and corresponding solutions are propsed.