Abstract: Acid hydrolytic corn starch was prepared with hydrochloric acid hydrolysis method by taking corn starch as raw material. The influences of acid hydrolysis temperature and time duration on structure and properties of the acid hydrolytic corn starch were studied. The crystallinity, gelatinization viscosity, gelatinization temperature and the thermal performance of the acid hydrolysis starch were analyzed by X ray diffraction (XRD), rotational viscometer, differential scanning calorimetry (DSC) and thermo gravimetric analysis (TGA) respectively. The results showed that the crystallinity and gelatinization temperature were increased first and then decreased along with the increase of acid hydrolysis temperature and time duration. Gelatinization viscosity was rapidly decreased with the increase of acid hydrolysis temperature and time duration. The thermal stability of corn starch was slightly influenced by acid modification.