Background: Hepatitis B infection is a major worldwide health issue.  Based on existing studies the rate of positive HBsAg cases is varied in different regions of Iran, and does not have the same distribution. It varies from 1.7% in the Fars province to 5% in the Sistan-Baluchestan province.  Hence, this study was carried out to investigate the positive HBsAg cases reported to the Health Deputy of Mazandaran University of Medical Sciences in 2008. Methods: In this study existing data were used. We used a standard form to extract data, which included variables such as age, sex, and marital status, place of residence, occupation, vaccination history, clinical symptoms, and history of risk factors. The data was analyzed by SPSS 16 software. Results: From the 577 reported cases, 57.9% were male, 75.4% were urban residents and the rest lived in villages, 79.9% were married. The average age was 37.9 ± 15.6.  Most of the women (68.8%) were housewives and most of the men (59.8%) were self-employed, and 99.1% had no history of vaccination. Conclusion: The prevalence of positive HBsAg cases in Mazandaran according to age, sex, marital status, place of residence, occupation and history of vaccination was consistent with most studies, particularly with the two comprehensive reviews.