Hepatitis viruses may cause liver cancer (HCC) through an indirect mechanism inducing inflammation and cirrhosis. Only hepatitis B virus (HBV) was shown to have a direct oncogenetic potential. Hepatitis D virus (HDV) infection, superimposed on the oncogenetic background provided by chronic HBV infection, appears to provide an additional risk for HCC. Patients with florid infections from both HBV and HDV and active liver inflammation develop HCC at a significantly younger age than those infected by HBV alone or infected by hepatitis C virus (about 10 years earlier). In patients positive for serum HBV-DNA/HDV-RNA and/or IgM anti-HBc/IgM anti-HD it is mandatory to program a more frequent (thrice a year) schedule of screenings (ultrasound scan, alpha-1-phetoprotein, etc.) for prophylaxis of HCC.