The invention belongs to the field of building enclosure wall materials, and particularly relates to a graphene and stone tailing-based foamed lightweight high-temperature-resistant wallboard and a preparation method thereof. The wallboard comprises the following raw materials in percentage by weight: 40-65% of stone tailings, 0.05-15% of graphene, 1-30% of aluminum oxide, 1-15% of vermiculite, 0.05-10% of calcium carbonate, 0.05-15% of high temperature solvent, 5-30% of high-temperature resistance fiber grains, 0.05-5% of vesicant, 0.05-5% of stabilizer, 0.05-5% of dispergator, 1-10% of clay,and additional 0-5% of pigment. The wallboard has the advantages of integrating comprehensive anti-ageing, anti-corrosion, heat-insulation, soundproof, waterproof and anti-seepage, fireproof, 1000DEGC high-temperature-resistant properties, light weight and high strength and toughness, no cracking, environment protection and the like, and the preparation method is simple and easy to operate, theproduction process is green and low-carbon, high-efficiency, energy-saving and consumption-reducing, and high in automation.