The "5·12" Wenchuan earthquake has induced many secondary geological disasters and directly threatens the life of the victims.So,it is very important to adequately understand secondary geological disaster and take effective emergency measures.This study is based on the field investigation of Tianjiaba landslide in Qingchuan County.The landslide is found to be an over burden landslide and is in latent instability,which is still in the instability during rainstorm and strong aftershock.The area influenced by the landslide is determined in view of landslide kinematics.The emergency measures of relocation,crack filling,and simple monitoring are taken.All the works are of important significance to the secondary geological disaster prevention after earthquake.