Abstract: As a typical representative of mine solid waste, the resource utilization of coal gangue is of great significance to environmental protection and engineering safety. Grouting technology is the key means of coal gangue filling and reinforcement, and the grouting pressure has an important impact on the grouting performance. Through the method of experimental analysis, this study systematically explored the influence of grouting pressure on slurry diffusion performance, permeability and crack control, solidification performance, fluidity and grouting efficiency, as well as the correlation between formation pressure and grouting pressure. It is found that the grouting pressure has a nonlinear positive correlation with the diffusion radius. When the pressure increases by 0.5 MPa, the diffusion radius increases by 15%～25% on average, and 3.0 MPa is the inflection point of efficiency; There is a pressure threshold of 2.5 MPa for the seepage behavior, beyond which the crack width increases by 20%～30%, and the slurry loss can reach 10%～15% of the total grouting amount; The solidification performance is the best under the pressure of 1.5～2.0 MPa, and the 28 day compressive strength is 12.5mpa; The formation pressure affects the critical grouting pressure, so it is necessary to maintain the pressure difference between 0.8 and 1.2 MPa to balance the diffusion effect and formation stability.