Abstract: “Digital Landslide” Technique(DLT) is a new developing technique for landslide remote sensing,based on the earlier work in the early stage and supported by modern information technique.At 14:00 2004-09-05,a large scale landslide occurred in Tiantai Town,Sichuan Province,China.By using DLT and satellite data of IKONOS(received before landslide occurring) and QUICK BIRD(received after landslide occurring) the landslide had been investigated in detail.Data of the boundary,size,direction and distance of the displacement of sliding blocts,position and volume of loading and unloading,and so on were obtained.Then,based on the principle of landslide-geoscience the spatial analysis was made.It was considered that although there were basic conditions of lithology,tectonic,and facing space to develop a landslide for Tiantai Town slope,which still had been a stable slope before 2004-09-05 landslide,the 2004-09-05 landslide was the first large scale movement and the slide was regressive;with a volume about 23 million m3.It was deduced that high way constructed on November 2003 was the potential inducing factor and the continuous heavy rain was the direct triggering factor for occurrence of 2004-09-05 landslide.