The invention relates to the technical field of volatile organic compound waste gas treatment, in particular to a preparation method of fused salt patch for adsorbing VOCs solid waste and special for a thermal-storage fluidized combustion furnace. The preparation method is characterized by comprising the steps of mixing based on a roller press, press forming, stationary ageing mixture, curing and drying, vacuum sintering and the like. Pollutants containing Cl-, SO2 and particulate matter in high temperature flue gas can be effectively purified, high-temperature corrosion and erosion abrasion to heated-surface metal components are avoided and decreased, and the service life of the heated-surface metal components is prolonged.