Purpose : To evaluate the accuracy of preoperative segmental localization of hepatic lesion by conventionalcomputed tomography (CT). Materials and Methdos : Thirty nine masses of hepatocellular carcinoma in 36 patientswere included in this study. We retrospectively compared the extent of involved segments by CT with that ofsurgery. In case of disagreement between CT and surgery, we classified as overestimation, underestimation andmismatch. And we calculated the accuracy of localization of each hepatic segments by CT. Result : The rate ofagreement between CT and surgery was 61.5% (24/39). In cases of disagreement, we overestimated in 7 (18%),underestimated in 3 (7.7%), and made a mismatch in 5 (12.8%). Segment I,II and III showed the highest accuracy(100%), but segment Ⅶ showed the lowest accuracy (88.6%). Conclusion : Preoperative localization of hepaticlesion in conventional CT is limited in sensitivity (61.5%), especially in the right lobe. Consequently othercomplementary studiss such as dynamic CT and hepatic angiography are helpful for preoperative localization.