Abstract: The data of mobile gravity measurement in Tangshan region are processed from 1981 to 1997. Analyzing gravity changes before and after Tangshan earthquake, it indicates that no similar gravity anomaly appeared in Tangshan region 20 years after the earthquake, and the gravity value has gradually return to the normal level within 10 years after the earthquake. The result shows that there was the gravity anomaly certainly existed before Tangshan earthquake and there was similar gravity change before the Guye earthquake with M_L 5.4, 1995, in this area.

Key words: Tangshan earthquake, Gravity, Anomaly