Aiming at the characteristics of high salt content and COD (chemical oxygen demand) of landfill leachate in domestic waste landfill, a feasible landfill leachate solidification method is proposed in this paper. By adjusting the dosage, composition and proportion of curing agent, the mass ratio of leachate to solidified matrix (liquid-solid ratio) can be controlled to realize harmless and stable treatment of landfill leachate. The results show that when the ratio of blast furnace slag to portland cement is 2:3 and the solid-liquid ratio is 0.9, the COD fixation rate in domestic waste landfill leachate is the highest, which is 68.74%, and the conductivity is the lowest, which is 16.7. By replacing a part of slag cement curing base with fly ash, and using a proper amount of water glass for alkali excitation, the alkali-activated slag can be obtained, which can increase the fixation rate of COD to 87.41%, reduce the conductivity to 10.02, and the fixation rate of Cl^- to 73.62%. The rational use of metallurgical waste for curing can reduce the harm of leachate, so that the leaching concentration of pollutants of the curing base can meet the requirements of safe landfill. The results of this paper can provide a feasible method for the treatment of high COD and high salinity leachate.