A dentine calcification agent which comprises tetracalcium phosphate particles (A) and an alkali metal phosphate (B), characterized in that the content of the tetracalcium phosphate particles (A) is 1 to 80 parts by weight per 100 parts by weight of the total dentine calcification agent, and the content of the alkali metal phosphate (B) is 1 to 100 parts by weight per 100 parts by weight of the tetracalcium phosphate particles (A). Thus, a dentine calcification agent, by which a dense HAp layer can be formed on the surface of the dentine and HAp can be deposited even in deep parts of dentinal tubules to thereby block the dentinal tubules, is provided.