Hepatocellular carcinoma (HCC) is the most common hepatic malignancy worldwide. The primary risk factor for the development of HCC is cirrhosis. Even patients without cirrhosis who develop HCC are typically found to have some underlying hepatic abnormality, such as steatohepatitis or chronic viral hepatitis. Although cirrhosis of any cause increases the risk of developing HCC, cirrhosis associated with chronic hepatitis B or C virus infection or hemochromatosis carries the greatest risk. Additional factors such as patient age and sex, duration and severity of liver disease, concurrent alcohol or aflatoxin exposure, liver histology, and alpha-fetoprotein levels also contribute to the relative risk of developing HCC. Vaccination programs aimed at preventing hepatitis B virus infection have been very successful in lowering the incidence of HCC in some areas of the world. Interferon-based therapy, which may control the inflammatory activity in chronic hepatitis C, also holds promise in preventing HCC. Other novel chemopreventative agents, such as glycyrrhizin and polyprenoic acid, may also have a role in preventing HCC, but they require further study before they can be recommended for widespread use.