摘要:Introduction: Because of the increased risk of chronicity of hepatitis B in HIV infected patients, immunization against HBV is recommended in patients infected with human immune deficiency virus. This study aims at determining the factors which affect the response to HBV vaccination in Iranian HIV positive adults, compared with a healthy control group. Methods: From April 2007 to May 2008, 50 HIV+ and 50 healthy control subjects who were seronegative for HBV received 3 doses of hepatitis B vaccine at 0, 1 and 3-month points. About 1-2 months after the last dose of vaccine, HBS antibodies were tested in the two groups. Persons were considered vaccine responders if their HBS antibody levels were greater than 10 mIU/ml. Results: In the HIV+ group 40 cases (80%) were vaccine responder and in control group, 46(92%) people responded to vaccine .The difference between the two groups was not statistically significant (P=0.8). There were no significant relationships between age, gender, BMI, smoking, alcohol drinking and the method infection and HARRT treatment. In the HIV group vaccine response was associated with CD4 count level (P=0.03). Conclusion: HIV infected patients are recommended to be HBV vaccinated at the regular doses and intervals. If CD4 count is less than 200/μl, HBS antibody should be tested in certain period for HIV+ individuals