Abstract: In order to study the influence of deformation of a goaf on the deformation and failure process of a rocky slope in valley area, the Xiaoeryan slope in Qingzhen City, Guizhou Province was taken as the research object, and the physical model test of bottom friction was used to set up the physical model, in which prefabricated fracture group and non-prefabricated fracture group were made respectively.We studied the failure process of the rocky slope under influence of goaf deformation, and discussed the deformation failure mode.Preliminary research found that:(1) The common point of the two experiments was that the goaf caused the deformation of the Xiaoeryan slope.The Xiaoeryan slope was a gently inclined slope of upper hard and lower soft structure, and the overlying roof of the goaf was bent and deformed under the action of gravity, leading to goaf sink.(2) The general deformation evolution process of the non-prefabricated fracture group model was mined-out subsidence, tensile fractures appearing in the slope, and the fractures extending to top of the slope.(3) The overall deformation evolution process of the prefabricated fracture group model was the goaf subsidence, the unloading fracture penetrating to the toe of the slope, and collapse occurring.(4) We believed that after prefabricating unloading cracks on the slope body, the unloading cracks had a great impact on the deformation mode of the slope.The geomechanical mode of deformation and failure of Xiaoeryan slopes can be divided into 2 stages of superficial transformation and fracturing-toppling(or splitting-dumping).