The invention discloses an ore tailings ceramsite air brick and a preparation method thereof. The ore tailings ceramsite air brick is prepared from the following raw materials in parts by weight: 20-30 parts of slate, 30-50 parts of coal gangue, 15-20 parts of building rubbish, 10-15 parts of modified loess, 8-12 parts of quicklime powder, 15-25 parts of ore tailings, 5-10 parts of rice husk, 8-12 parts of barite, 10-15 parts of limestone, 5-10 parts of volcanic ash, 3-6 parts of aluminum silicate fiber, 2-4 parts of calcium sulfate whisker and a defined amount of water. According to the invention, ore tailings are taken as the main raw material to prepare ceramsite to produce the air brick, which not only reduces a great amount of cultivated land occupied by accumulated iron ore tailings and environment pollution, but also improves the heat-insulating property and mechanical strength of the air brick. The air brick provided by the invention has the advantages of high strength, low density, good heat-insulating property, anti-seismic property and weatherability, environmental friendliness, energy conservation and the like and is suitable for large-scale popularization and application.