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Background: Chronic hepatitis B virus (HBV) infection is a multi-factorial disease that is accompanied with serious clinical complications. Host’s genetic background, especially immune–genetic factors, is critical in the pathogenesis of infection. Gamma interferon ((INF-γ) and its receptor have an important role in immune response to the virus and clinical course of the disease. The aim of this study is to investigate the association between single nucleotide polymorphism -611G/A located in promoter of gamma interferon receptor1 gene (INFGR1) and chronic HBV infection. Materials and Methods: In this Case Control study, genomic DNA from peripheral blood samples of 150 chronically HBV infected patients and 150 healthy controls was extracted by phenol-chloroform method. DNA analysis was performed by PCR-RFLP method and P<0.05 was considered significant. Results: After stages of genotyping and statistical analysis, a significant difference was observed between patient and control group, so that genotype GG was higher in the control group compared to the patient group. Conclusion: The host’s immune-genetic background can play an important role in the pathogenesis of infectious disease. Variations in INFGR1 were related to several diseases. The results showed that the presence of GG allele is accompanied by a decrease in susceptibility to chronic HBV infection.