Three hundred and sixty-eight case-control sets (male 287 pairs; female 81 sets) were collected for a hospital-based case-control study of primary hepatocellular carcinoma (HCC) conducted in Northern Kyushu, Japan. All incident cases of HCC were collected weekly from the inpatients (aged 40–69) of the Second Department of Internal Medicine, Kurume University Hospital between April, 1986 and May, 1992. One control for a male case and 4 controls for a female case were sampled, being matched to a case on age (same 5-year age class), sex, residence (prefecture) and time of hospitalization (within 2 months after a case interview) from the inpatients of two general hospitals in Kurume. Information was collected by interview in person by a well-trained interviewer and from a review of hospital records by the authors. Multivariatc analyses based on a conditional logistic regression model without an interaction term revealed that hepatitis B surface antigen (HBsAg) positive status (odds ratio (OR) = 8.67; 95% confidence Interval (95%CI) = 2.54–29.57), history of blood transfusion over 10 years previously (2.40; 1.26–4.56), parental history of hepatic diseases (2.31; 1.11–4.80) and heavy alcohol drinking (60≦ drink-years) by age 40 (3.23; 1.61–6.51) were statistically significant risk factors of male HCC. Univariate analysis for females also showed an elevated OR of HBsAg (7.58; 1.96–29.35). Although the sample size was limited, univariate analysis indicated that anti-hepatitis C virus antibody by c100-3 antigen positive status had a statistically significant OR for HCC in both sexes.