Abstract: The seismic activity characteristics and causes of earthquakes in eastern Tibet were studied in this paper. It is shown that the seismic activity in this area presents a trend of cumulative enhancement, which is related to seasonal rainfall. When the rainy season coming, the frequency of seismic activity increases obviously, and the crustal movement becomes more intense. This may be related to the change of groundwater system after the increase of rainfall density, which promote the occurrence of earthquakes. Therefore, it is recommended to strengthen monitoring and study of groundwater systems before the rainy season to provide early warning of earthquake possibility. In some areas where earthquakes occur frequently, ground subsidence will occur in a short time before earthquakes. This kind of surface subsidence may be caused by deformation and fracture of underground strata, which is one of the signals of impending earthquake. Therefore, monitoring the change of surface subsidence can judge the possibility of earthquake in advance and take corresponding early warning and disaster prevention measures. Further research has also revealed factors that may influence seismic activity. By analyzing the geological structure and fault characteristics, it is found that there are many fault zones of strata in eastern Tibet, which form the factors of seismic activity. The existence of these fault zones will not only strengthen seismic activity, but also restrict the propagation of seismic waves and increase the severity of seismic disasters near the source area.