Hepatitis B virus (HBV) is a partially double spiral type DNA virus. Globally, approximately over 400 million individuals are infected with hepatitis B. HBV is known as one of the most important carcinogens. Every year, over one million individuals die due to HBV-related causes. Perinatal transmission is believed to be the most important mode in regions of developing world with high and intermediate HBV prevalence rates. HBV remains a major nosocomial pathogen in many hospitals. Transmission may occur due to unsafe injections, blood transfusions and lack of awareness of infection control. Sexual contact also accounts for some HBV transmission. The spectrum of disease and natural history of chronic HBV infection is diverse and variable, ranging from a low viremic inactive carrier state to progressive chronic hepatitis, which may evolve to cirrhosis and HCC.