Abstract: Based on systematic analysis,nine seismometry parameters that response earthquakes well in North China are selected,which are seismic frequency,seismicity scale,mf-value,b-value,D-value,η-value,seismicity intensity entropy and seismicity time entropy.Using synthetic anomaly index method,we calculated their seismic anomaly index values separately and synthesized these values into a chronogenesis curve.After studying its short-term anomaly characteristics to earthquakes,the criterion index for M_L≥5.8 earthquakes in North China is obtained.The R-value test indicts that it has good prediction effect.