In this study，we analyzed co-seismic responses of water level in the Jiaji well during the strong earthquakes ( MS ≥7. 8 ) from 2001 to 2010 with the epicentral distance less than 8000km. We counted the co-seismic form of the water level，and analyzed the relationship among the amplitude of water level，the magnitude and the epicentral distance，and then checked the seismic wave phases during the changes of water level． It was shown that : (1 ) the co-seismic forms of water level mainly represented step-increase with no oscillation; ( 2 ) the amplitude of water level had a certain connection with epicentral distance and magnitude; ( 3 ) co-seismic responses of Jiaji well showed a certain direction，;(4) the most of co － seismic responses were caused by surface waves，some of which had long period．