Abstract: To reveal collapse mechanisms of shattered slope under wind loading, the slope stability assessment system was built. Based on the field survey of shattered slopes and valley wind measurement, the large-scale wind tunnel tests in various conditions were conducted by using Shidaguan collapse as an example. The results indicate that Shidaguan collapse is a typical case of shattered slope collapsing in a sudden burst under wind loading. This mode of collapse are hardly controlled by structural plane because of the unique slope structure. Meanwhile, since the distribution of river valley wind is affected by the topographical elements, it becomes complicated and varied. Thus the sudden collapse mode undergoes fast breakdown-crumbling-collapse as a whole, quite distinct from slope failure mechanisms under general gravity force. The loosing and cracking of the rock masses is fundamental to the collapse, while the gradual weathering is the main factor. Besides, the strong river-valley winds aggravate the collapse. Furthermore, the wind speed leading to rock masse instability is in inverse proportion to wind incident angle, as well as the height-width ratio of mass, and the width of the trailing edge crack.