The invention discloses a high-strength 
cement-based self-leveling 
mortar prepared by desulfurization 
calcium plaster, and belongs to the technical field of self-leveling 
mortar. The high-strength 
cement-based self-leveling 
mortar prepared by desulfurization 
calcium plasteris prepared from the following raw materials in parts by weight: 18 to 28 parts of desulfurized 
calcium plaster, 30 to 37 parts of 
aluminate cement, 5 to 6 parts of 
Portland cement, 35 to 39 parts of natural siliceous sand, 0.7 to 0.8 part of water 
reducing agent, and 0.01 part of thickener. The invention further discloses apreparation method of thehigh-strength cement-based self-leveling mortar prepared by the desulfurization calcium plaster. According to the high-strength cement-based self-leveling mortar prepared bythe desulfurization calcium plaster and the preparation method thereof, the performance characteristics of the desulfurized calcium plaster, high-
alumina cement, and the ordinary 
Portland cement are fully utilized respectively, the prepared cement-based self-leveling mortar has the characteristics that the setting and hardening speeds are fast, fracture resistance and crush resistanceof early andlater periods are high, 
wear resistance is good,the surface is not prone to being pulverized, and 
impact performance is good; the plasterin the desulfurized calcium plaster is not subjected to treating processes such as pressure 
filtration and 
drying, so that the dispersion effect of the desulfurized plasterin 
cement slurry is better, the production cost is lowered, new approaches are provided forpreparation of cement-based self-leveling mortar and 
resource utilization of desulfurizedcalcium plaster,and economic and environmental benefits are good.