Collapse hazards are frequent in the Sichuan-Tibet Transportation Corridor of Dongcuoqu Basin which is a significant geological risk source for the construction and safe operation of major projects in eastern Tibet. Based on field investigations，the distribution patterns and developmental characteristics of collapse disasters in the study area were summarized， and the formation mechanisms and evolution model of the collapse-debris flow hazard chains were analyzed. The results show that the collapse disasters in the Dongcuoqu Basin has a banding distribution along both sides of the river and faults in space， and concentrately distributed in the lighter and harder strata. The vertical distribution of the collapse is mainly controlled by the convex folded slope morphology and elevation. The development characteristics of collapse are caused by the slope structure， which led to 3 collapse models namely bending-toppling-type， pulling-sliding-type and composite-type. The collapse in the region is featured of high-altitude initiation and remote movement， and the scale of the collapse is significantly influenced by the elevation， height difference and gradient of the collapse source area， while the grain size and movement distance of the deposits are closely related to the lithology. The collapse disasters in the area have a typical chain-type evolution process of collapse-debris flow-river blocking， and the disaster and chain generation process is mainly controlled by factors such as freeze-thaw and topography， among which the giant collapse-debris flow hazard chain is mainly triggered by earthquakes. The research results can provide reference for the prevention and control of landslide disaster risks in human engineering activities in the area.