Hepatitis B virus (HBV) is a DNA virus from the Hepadnaviridae family. These are pathogens only for humans and some apes. Most acute viral hepatitis is caused by hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV) and hepatitis D virus (HDV) virus. Six hepatitis viruses are known as A to G. Hepatitis represents a common term and indicates liver inflammation. The most common causes of hepatitis are viruses, but certain types of hepatitis can cause various toxic substances (alcohol) or autoimmune diseases. Infected blood is the most common source of infection. Also, the virus can befound in the bile, seed, vaginal secretion, breast milk. The greatest risk of infection is direct virus entry directly in to the blood stream. Hepatitis B is a major public health problem worldwide. It is estimated that approximately 400 million people worldwide have a chronic infection. It is also estimated that more than 500,000 people per yeardie due to hepatitis B infection. The route of transmission and response to infection varies depending on age at time of virus infection. Therefore, it is well known that most people infected during early childhood develop chronic infections, remain carriers and they are more prone to development of hepatocellular carcinoma in adult age.There are over 250 million carriers, and 25% of them develop chronic hepatitis. People are the only reservoir of hepatitis B virus. Hepatitis B infection is among the 10 leading causes of mortality from infectious diseases in the world. Death occurs after liver failure or liver cancer. 50% of all liver cancers are associated with chronic hepatitis. Since mandatory of HBsAg testing volunteer blood donors has been introduced, it happened a dramatic reduction in the number of hepatitis cases associated with blood transfusions and blood products. Oral transmission is not proven. It can be assumed that all body fluids of a person infected with HBV are potentially infectious.