The invention relates to the field of environmental protection, and belongs to the field of preparation of mullite automobile exhaust purification catalyst carriers. Kaolin, alumina powder and mullitecellucotton are used as raw materials, and the automobile exhaust purification catalyst carrier is obtained through ball milling, suction filtration, mixing, 3D modeling, 3D printing, drying and sintering operations. The 3D printing mullite automobile exhaust purification catalyst carrier product is controllable in surface area, good in catalytic effect, high in catalyst carrier strength, high instructural density and high in thermal stability, and satisfies the multi-period alternate cooling and heating use environment of an automobile exhaust pipe.