Abstract: The coseismic response of digital data,which observed by 43 precursor items in Zhangjiakou,Huailai,Chicheng,Kuancheng,Yixian and Shexian seismostation,to the 3 over 4 magnitude earthquakes occurred in Xingtai area from 2002 to 2005 is studied.The results show that the seismic response concentrated in strain data,including body strain and linear strain.The anomaly shape mainly is tidal aberrance and dithering.Coseismic response is clear and mainly showed in jump shape.