<p>The internal fissures and micro-defects of the rock mass have a decisive influence on the damage characteristics of the rock mass under high stress conditions. In order to investigate the macroscopic and microscopic damage characteristics of the fissured laminated surrounding rock under high and low confining pressures, the RMT-150&#xa0;C is used to carry out the conventional uniaxial and tri-axial tests in the dry state, and the SEM scanning is performed on the crushed test specimens, so as to analyze the damage characteristics of the rock mass from the macroscopic angle and the microscopic angle. The study shows that the fracture of the rock mass is mainly due to the progressive extension of the original cracks in the rock mass plus the generation of secondary cracks, which is the result of the two complementing each other. The size of the confining pressure has a very great influence on the damage form of the rock mass. Using RFPA software to simulate the confining pressure, it can be obtained that the macroscopic crushing of the material is a qualitative change obtained by the accumulation of internal micro cracks that continue to develop and change. Using SEM electron microscope scanning through observation can be obtained that the development of microfractures in different directions and mainly tensile, fissure rock mass after complex geological effects, microfractures overlap each other, the fissure area is expanded, the stronger the connectivity of microfractures, the more prone to intersect with the damage surface of the fracture along the crystal.</p>