Abstract: Based on the seismic data of Heze, Jariang and Liangshan stations from 1979 to 1985, where the earthquakes occurred in Heze could be recorded, the attenuation coeffcient K for the seismic coda wave of three components aud vertical component has been computed and their variations before and after Heze Ms5.9 earthquake have been analysed. The results have shown that the coda wave atten-uation coefficient of the three components and the vertical component at these stations obviously displyed anomalous low value before the event. The anomaly duration reaches to 21 months. The minimum decreases nearly by 50%, The attenuation coefficient returned to the normal value after the event.