Background and aims: Hepatitis B virus (HBV) is one of the important public health diseases in Iran. Therefore, to control the prevalence of the disease, knowledge is required regarding the risk factor of HBV. Accordingly, the aim of this study was to determine the risk factors of HB transmission. Methods: A retrospective case-control study was conducted on the possible risk factors of HBV transmission. To this end, a total of 171 patients with HBV infection and 171 controls from Rasoul-eAkram hospital were investigated during 2015-2018. All subjects were directly evaluated using a faceto-face questionnaire about demographic aspects. Finally, HBV infection and its risk factors among the subjects were detected using hepatitis B surface antigen test. Results: Overall, 171 HBV patients including 77 (42%) males and 93 (58%) females were evaluated. The mean age of the participants was 40 ± 13 years. Univariate logistic analysis showed that HBV infection in these cases was associated with addiction injection (odds ratio [OR] = 4.08, CI:1.3- 9.57), family history (OR = 4.52, CI: 1.27-10.7), and having a history of blood transfusion (OR = 3.16, CI: 1.52-5.37). There were no significant relationships between the liver function tests, alcohol consumption, the history of dental visits, and HBV participants. In addition, the logistic-regression model proved that patients with a history of HBV-infected parents (At least one of them) and addiction injection were severely subject to HB infection. In other words, there was a significant association between a history of HBV-infected parents and addiction injection and HB infection. Conclusion: In general, HBV infection was strongly related to having a family member infected with hepatitis B, suffering from addiction injection, and having blood injection.