116 large scale landslides develop between Lagan Gorge and Sigou Gorge in the upper reaches of the Yellow River. And there, Qunjian basin has an edge over others in quantity and intensity of landslide events, as has a direct correlation with the unique tectonic position and the characteristic change of the major fracture zone during Kun Huang movement epoch. The tilting uplift process of plateau causes more large scale landslides to occur in the west coast than the east coast along the major tributaries of river systems. Large scale landslides were triggered by the respective factors during 4 distinct phases, i.e. before 50km and 30km for the coupling cause of tectonic and climatic, before 10km by tectonic, and before 5km by rainfall.