BACKGROUND: Serumc alpha-fetoprotein(aFP) is a useful diagnostic test on hepatocellular carcinoma(HCC) However, it is still questionable appropriate screening test or not. METHODS: A total of 24,050 patients who visited the General Health Screening Center of Asan Medical Center from June, 1993 to June, 1994 were reviewed by chart and telephone survey. Among them 70 cases where serum aFP were elevated > 20ng/ml and 16 cases where HCC was suspected by abdominal ultrasonogram were selected and investigated for the existence of HCC. Four groups were divided into HBsAg(+), Anti-HCV(+), increased AST/ALT(abnormal LFT) and normal gruoup. Each group was evaluated for sensitivity, specificity, positive predictive value and negative predictive value of serum aFP for HCC. RESULTS: The prevalence of elevated aFP was 0.29%(70/24,050). There was a statistically significant difference between sexes. And the total number of HCC as 10 cases (42/100,000). With aging, the prevalence of HCC was increased. The prevalence rate of elevated serum aFP and HCC had significant difference in anti-HCV(+), HBsAg(+) and abnormal LFT group compared to normal group (sGOT < 40U/I, HBsAg(-) and Anti-HCV(-)) (P < 0.01). In our study, sensitivity and positive predictive value of serum aFP for HCC were 100% and 14% in anti-HCV(+) group, 83.3% and 8.6% in abnormal LFI group, 80% and 8.0% in HBsAg(+) group, and 0% in normal group, respectively. CONCLUSIONS: Serum aFP as a screening test for HCC in asymptomatic healthy people does not seem to be not valid. But it seems to be appropriate when it is applied for cases of abnormal LFT(sGOT > 40U/l or sGPI > 40U/l), HBsAg(+) and Anti HCV(+) people.