Hepatocellular carcinoma (HCC) is one of the most common cancer worldwide. Most of the HCC occur in developing countries. Chronic hepatitis B virus (HBV) infection is an important risk factor for HCC development. HBV induces immune-mediated chronic hepatitis, liver injury, regeneration and scar forming responses, leading to an inflammatory, fibrotic and immune deficient microenvironment. HBV may integrate into host genome, inducing genetic abnormality and altering the expression of HCC-related genes. HBV also expresses active proteins such as X (HBx) and S proteins, which may trans-activate HCC-related proteins expression, interact with intracellular specific proteins, activate a variety of signaling pathways, and induce aberrant epigenetic modifications. HBV mutation also has impact on HBV related HCC development.