The invention belongs to the technical field of preparation of ceramic water reducers and discloses a cyclodextrin grafted copolymer type ceramic water reducer and a preparation method thereof. The water reducer is prepared from cyclodextrin or a cyclodextrin derivative, 3-(2-methylacryloyl ethoxyl dimethylamine) propanesulfonate, a chain transfer agent, an initiator, a chain terminator and deionized water. Due to a special molecular structure of cyclodextrin, the water reducer prepared by the preparation method has very good water-reducing and dispersing effects and meanwhile the water reducer which is amphoteric ionic polyelectrolyte is good in chemical property and thermal stability, strong in hydratability and insusceptible to the pH value of a solution. In addition, the water reducer prepared by the preparation method provided by the invention further has an enhancing effect on ceramic.