As an groundwater monitoring well with high precision and sensitivity, YU 01 well in city of Fanxian, occurred obvious anomalies before many earthquakes. This plays an important role in monitoring earthquakes in the Hebei-Shandong-Henan area and neighboring regions. In this paper, correlation of the well and earthquakes activities will be analyzed, and make statistics of the well’s reflection on the earthquakes. Then conclude that this well reflect more sensitive on the earthquakes within 50km and exceed magnitude 4. Through this study, it will be helpful to distinguish the anomalies of the subsurface fluids in YU 01 well, and can predict origin time of earthquake easily。