Abstract: In order to solve the problem of deformation and failure of surrounding rock caused by long cantilever extrusion roadway, which is formed by thick and hard roof, this paper takes the typical working face of Caojiatan Coal Mine as the engineering background. The TRIZ theory was used for systematic analysis, and the cause of the deformation of the surrounding rock of the roadway was determined by the causal relationship method. The principle of spatial separation was used to separate the roof of the goaf from the roof of the roadway, and the roof of the goaf was softened by the pre-action method to achieve the purpose of timely caving and filling of the thick and hard roof. Based on TRIZ theory, a combined blasting technology of ' directional cumulative blasting + non-directional reinforced blasting ' was proposed. The key parameters of combined blasting were determined by theoretical analysis and verified by numerical simulation. On this basis, the combined blasting scheme was designed. Finally, field engineering tests were carried out. The field application results show that the problem of deformation and failure of roadway surrounding rock is effectively solved by using combined blasting technology.