PURPOSE: To obtain a calcium phosphate composition curable at a curing rate accelerated by laser light irradiation to give a cured product having improved hardness and strength and useful as a dental cement material, etc., by kneading an aqueous solution of phosphoric acid with calcium phosphate giving a hydroxyapatite composition.

CONSTITUTION: The objective cement composition can be produced by compounding (A) tetracalcium phosphate powder and (B) other calcium phosphate powder (e.g. calcium phosphate dihydrate, tricalcium α-phosphate or tricalcium β-phosphate) at a ratio to give a hydroxyapatite composition (Ca/P=5/3), adding hydroxyapatite powder as a seed crystal and homogeneously kneading the mixture. The kneaded product is used as the calcium phosphate composition and formed to a desired shape. The formed product can be cured by irradiating with a laser light (light having wavelength of 1300-800cm-1, especially 700-500cm-1).