Physicochemical properties on defatted potato starches, Irish Cobbler and Dejima, were investigated. The average diameter of the Irish Cobbler and Dejima starch were $22.5-29.8mu extrm{m}$, and both the starches had birefringence. Irish Cobbler starch was lower than that of Dejima starch in water binding capacity, swelling power and solubility. Relative crystallinity of both the starches was decreased after defatted. The blue value of Irich Cobbvler and Dejima starch was measured 0.37 and 0.35 respectively Transmittnace of 0.1% starch suspensions was higher on defatted starch than on untreated starch. Differential Scanning Calorimetry of untreated potato starch showeed higher gelatinization temperature in Irish Cobbler starch than in Dejiam starch. The gelatinization enthalpy of untreated starch was higher in Irisch Cobbler starch than in Dejima starch, but, after defatted, it was decreased.