The invention discloses an ultra-fine solid waste-based grouting material and a preparation method thereof, aiming at solving the problem that the micro-cracks existing in the cement-based grouting material are difficult to inject, have poor stability, are easily washed away, have high water separation rate and low stone rate , Long coagulation time and difficult to adjust, slow strength growth, large shrinkage and other technical problems. It is mainly composed of solid waste ultrafine powder, calcined solid waste ultrafine powder, calcium-increased calcined solid waste ultrafine powder, alkali-containing substances, waste sulfate minerals, inorganic salts, thixotropic components, and plastic expansion components. , fluidized components, coagulation components and other raw materials are prepared through the steps of powder mixing and auxiliary addition. The prepared grouting material has good stability, thixotropy, injectability, adjustability of setting time, mechanical properties and durability, energy saving and environmental protection, and is suitable for road subgrade diseases, mining goaf backfilling, anti-seepage blocking Leakage, rock (coal) seam reinforcement and other treatments.