To provide a catalyst which is capable of exhibiting a higher gas purification function than the catalyst of conventional technology while utilizing molding sand, and to provide a catalyst carrier which can form the catalyst carrier utilizing molding sand and which enhances gas diffusibility and to provide its manufacturing method.

The catalyst carrier is prepared by having an alumina layer formed on the surface of a porous material which is formed by the molding sand and the gas diffusibility can be enhanced at the inside due to pores of the porous material. The manufacturing method of the catalyst carrier comprises granulating the kneaded material by adding water to the molding sand to obtain the granular, then forming the porous material by calcining its granular and further forming the alumina layer on the surface of the porous material. The catalyst which is illustrated separately is to carry the catalyst material on the catalyst carrier and has the high gas purification function (removability).