Method of manufacturing cerium-based polishing agent

This invention aims to provide a method of manufacturing a cerium-based abrasive containing coarse particles in lower concentration and having higher polishing ability and excellent cleanability for a polished face. Further, the present invention provides a method of manufacturing a cerium-based abrasive, including the steps of pulverizing a raw material, roasting a raw material after pulverization and disintegrating a raw material after roasting, in which a cerium-based rare earth carbonate or a mixture of a cerium-based rare earth carbonate and a cerium-based rare earth oxide is used as a cerium-based abrasive raw material, and the step of pulverizing a raw material pulverizes a raw material through heating while the material is kept immersed in aqueous solution.