In order to evaluate the seroepidemiology and response to Butang® vaccine in adolescents from low income families in Central Brazil, blood samples of 664 adolescents were tested for hepatitis B surface antigen (HBsAg), hepatitis B core antibody (anti-HBc), and hepatitis B surface antibody (anti-HBs) markers, and multiple logistical regression analysis was carried out to determine variables associated with hepatitis B virus (HBV) infection markers. Further, three 20 µg Butang® vaccine doses were offered to all susceptible individuals (n = 304). Among those who accepted them (n = 182)Hepatitis B virus (HBV) has been considered a global health problem. This has been cause of acute and chronic hepatitis, cirrhosis, and cancer of the liver (Mast et al. 2005). It is estimated 2 billion people have been infected and that more than 350 million of individuals are chronic carriers of HBV worldwide (Hou et al. 2005). Also, this infection has been answerable for 520,000 deaths each year (EASL 2003).In high endemic regions, hepatitis B is transmitted mainly by vertical or horizontal mode. In contrast, in low and intermediate endemic regions, it is disseminated generally by sexual and parenteral via (Hou et al. 2005, Mast et al. 2005 whereas an increase of HBV positivity throughout the adolescence and early adulthood was showed (Dominguez et al. 2000, Cisneros-Castolo et al. 2001, Gaze et al. 2002. During this period of life individuals are more susceptible to risk behaviors such as illicit drug use, alcohol abuse, multiple partners, and sexually transmitted diseases (Lawrence & Goldstein 1995, Miranda et al. 2005). Also, a higher risk of hepatitis B has been observed in economically disadvantaged adolescents (Porto et al. 1994, Silveira et al. 1999, Clemens et al. 2000, Gandolfo et al. 2003. Hepatitis B vaccination is the most effective strategy for HBV prevention. In Brazil, it has been available in private clinics since the beginning of 1990s, but due the elevated cost of doses only individuals with better socioeconomic conditions could be vaccinated. In 1999, in compliance with WHO recommendations (WHO 2003) the Brazilian Public Health Authorities implemented the universal hepatitis B vaccination for newborns and infants, and more recently it was extended for adolescents.Actually several countries manufacture the hepatitis B vaccines. This should play a role in the cost of doses and to improve the worldwide hepatitis B vaccine coverage, mainly in developing regions (Vryheid et al. 2000). Butang® is a Brazilian hepatitis B recombinant vaccine (Ioshimoto et al. 1999). It has been provided free of charge by health public services since 2001. However, there is still few informations about the immunogenicity of this vaccine in different groups (Baldy et al. 2004, Martins et al. 2004.In order to assist decisions on strategies for hepatitis B vaccination in a target group of the Brazilian immunization program, an investigation was carried out to evaluate the prevalence and risk factors for HBV infection, the adherence to and the...