Hepatic masses show different enhancing patterns in IV bolus computed tomography: Hepatocellular carcinoma shows high-attenuation in the early enhancing phase and low-attenuation in the late enhancing phase, hemangioma shows peripheral dot-like high-attenuation in the early enhancing phase and central high-attenuation in the late enhancing phase, and metastatic cancer and cholangiocelluar carcinoma show peripheral high-attenuation rim in the early enhancing phase and central portion gradulally high-attenuation in the late enhancing phase. but sometimes enhancing patterns of the hepatic masses are confuse. To evaluate the significance of the AFP level and HBsAg in differentiation of the hepatic masses, we retrospectively analyzed AFP level and HBsAg in 228 pathologically or radiologically confirmed hepatocellular carcinomas, and 137 pathologically nonhepatocellular cacinomas. The results were as follows : In hepatocellular carcinoma, AFP level above 20ng/ml was 77.8% and HBsAg positve was 72.6%. In nonhepatocellular carcinoma, AFP level above 20ng/ml was 3.7% and HBsAg positve was 16.1%. We concluded that AFP level and HBsAg are helpful to distinguish hepatocellular carcinoma from nonhepatocellular carcinoma, when IV bolus computed tomogram finding is uncertain.