The prevalence of antibodies to hepatitis C virus (anti-HCV) has been measured in 113 Saudi patients with chronic liver diseases. Twenty-five percent of 20 patients with hepatocellular carcinoma (HCC) were positive for anti-HCV and 29.7% of 38 patients with cirrhosis and 27.3% of 33 patients with liver fibrosis, respectively, also tested positive. The positivity rate for a miscellany of liver diseases (22) was 13.6%. The differences between these prevalence rates were not statistically significant. By comparison, 45% of HCC tested positive for hepatitis B surface antigen (HBsAg) while 52.7% of cirrhosis cases were positive. These rates were statistically significant when compared with HBsAg positivity rates of 9.1% and 18.2% in the liver fibrosis and miscellaneous groups. The role of hepatitis C virus (HCV) may be secondary or additive in the causation of chronic liver disease and hepatocellular carcinoma in this environment in which hepatitis B virus (HBV) is highly endemic.