With the virtue of high Young's modulus, fine thermal stability, low density, low price, resourceful and easy to be industrialized, alumina matrix ceramics are widely applied in the environments of high temperature, high pressure, radiation, impact, abrasion and corrosion, etc. The sintering process of large-scale alumina matrix ceramic products is researched in this paper. The conception of temperature gradient is introduced to the sintering process, and corresponding mathematics model is established to get the cellular girder made of alumina, in which the microstructure is distributed evenly. Meanwhile, the material structure and the mechanics performance of the products are discussed. All the study will theoretically guide the development of large-scale fine alumina products.