The physicochemical properties of acorn starch were investigated by comparing acorn crude starch and refined starch. Proximate composition analysis revealed that the contents of crude protein, fat and ash were higher in acorn crude starch than in refined starch. Water binding capacity and swelling power of crude starch were a little higher than refined starch. Gelatinization temperature determined by optical transmittance and by Amylograph were 68℃ and 73℃, respectively. The viscosity of crude starch had the amylose content of 28.8%, and the molecular weight of amylose was 20, 425 and glucose unit per segment of amylopectin was 21.