The invention discloses a method for preparing aluminum-silicon-carbon powder. The method comprises the following steps of: (1) weighing 49-60 percent by mass of corundum brick, 14-18 percent by mass of silicon brick and 26-33 percent by mass of carbon block serving as raw materials and mixing the raw materials to obtain a mixture; and (2) heating the mixture under CO protective atmosphere of 1 atmospheric pressure at the temperature between 2,300 DEG C and 2,800 DEG C for 4-6 hours, cooling and removing an impurity layer from the surface of a product to obtain aluminum-silicon-carbon powder. In the method, a waste refractory material is taken as a raw material, so that the production cost is lowered and the recycling of resources is realized; moreover, the method is simple, convenient and feasible and is suitable for large-scale production; and the yield and the purity of the obtained product are high.