The mean annual rainfall has increased 3-30% in the comparison of the rainfall records from 1961 to 1970 and from 2001 to 2008. The inducing factors for the landslide in Chishan river watershed include earthquake events, rainfall events, and the flood. The inducing influences of earthquake events to the landslide appear not only on on the steep up-hillslope, but also on the mild down-hillslope. The inducing influence of Chichi earthquake to the landslide in Chishan river watershed seems to be decreasing with progress of time, and the apparent inducing influence to the landslide on the down-hillslope due to the river scour during the heavy rainfall events can be found based on the landslide distribution from 2001 to 2008.