A cement hydration heat regulating material（HHRM）, which was prepared by pyrolysis and enzymatic hydrolysis of corn starch, was characterized by X ray diffraction（XRD）, scanning electron microscopy（SEM） and gel permeation chromatography（GPC）. Performance tests show that, the material has a porous structure with a higher degree of crystallization. When used in solid powder, it can reduce the cement hydration exothermic rate peak about 55%, however, when added in dissolved state, it only extended the induction period of hydration. It is proposed that reduction of the cement hydration exothermic rate peak is due to the HHRM slow releases polysaccharide chains to cement particles.