BACKGROUND/AIMS: We evaluated the usefulness of helical liver computed tomography (CT) in determining the necessity of biopsy for hepatic mass. METHODS: We collected 57 consecutive patients with hepatic mass identified with ultra sonography (US) guided biopsy. Hepatic masses were detected by both US and CT during follow-up examinations for chronic liver disease. We divided the patient into two groups according to CT findings. Group I included 43 patients with typical helical CT fin dings of hepatocellular carcinoma (HCC), and Group II included 14 patients with atypical findings Enhancement on arterial phase and hypoattenuation on portal and/or delayed phases were considered as typical findings of hepatocellular carcinoma. The results of phathological examination were analyzed by McNemar test. The level of alphafetoprotein was assessed. RESULTS: All of the Group I patient were found to have HCC in the pathological examination. In the Group II patients, nine patients had HCC, three had metastasis, and two had cholangiocarcinoma. The result was statistically significan (p=0.004). Additionally, 40 % of Group I and 36% of Group II patients showed elevated alpha feto protein level above 100 ng/mL. CONCLUSIONS: Focal hepatic mass showing typical helical CT findings of HCC does not need biopsy regardless of alpha fetoprotein level. We conclude that helical liver CT is very useful in determining whether biopsy is needed in diagonizing hepatic mass.