The invention relates to a honeycomb heat accumulator made of silicon carbide-corundum composite materials, which comprises the following main raw materials: 20-30wt% of silicon carbide powder, 4-8wt% of zirconia corundum powder, 20-30wt% of corundum powder, 15-20wt% of porzite powder, 15-30wt% of composition of kyanite, andalusite and sillimanite, 4-8wt% of kaolin and 2-5wt% of cellulose powder. The preparation method of the honeycomb heat accumulator comprises the following steps: adding the main raw materials into a ball mill for ball milling; adding stearic acid of which the weight is not greater than 1% of the total weight of the main raw materials for ball milling, and then, sieving to obtain a mixture; respectively adding tung oil of which the weight is not greater than 1% of the weight of the mixture and glycerol of which the weight is not greater than 1% of the weight of the mixture for mixing, aging and vacuum pugmill to form pug segments; carrying out extrusion forming in a mold, and drying; and insulating at the temperature of 1400-1450 DEG C for 4-8 hours, and then, calcining. The honeycomb heat accumulator of the invention has the characteristics of high fire resistance, good thermal shock resistance, strong corrosion resistance, large heat exchange area, small gas flow resistance, high heat accumulating efficiency, small floor space and long service life which can be more than two years, and is widely used for heat accumulating type heating furnaces of black and non-ferrous smelting, thermal power generation, petrochemical industry, ceramics, glass, machining, civil cookers and the like.