The accumulation of desulfurization ash from coal-fired power plants can lead to serious waste of land resources and environmental safety problems. This work presents an experimental study on the feasibility of recycling original desulfurization ash as the main raw materials, and a new green grouting material was prepared. The results indicate that a desulfurization ash-based grouting fire prevention material which was prepared according to the following ingredient design (a water-to-solid ratio of 1.0:1 and a hydroxyethyl cellulose content of 0.09% desulfurization ash, 12% quicklime, 0.6% Na2SO4, and 0.05% triethanolamine, 80 °C curing). The slurry's viscosity meets requirements, and its suspension, liquidity, and consolidation strength are better than those of clay under the same conditions. In addition, the grouting material's inhibitor ratio is increased with temperature increase, which means it has good flame retardancy. Environmental performance tests concluded that when desulfurization ash as-recycled admixture is used for the preparation of grouting fire prevention material, from the technique point of view, the environmental safety of them is very good.