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Background and Aims: chronic HBV infection is one of the most common viral infections in worldwide which many factors such as genetic factors are involved in pathogenesis of disease. Gamma interferon (IFN-γ) and its receptor (INFGR) play a critical role in the immune response to HBV infection. Single nucleotide polymorphisms (SNPs) are effective on level of gene expression, The aim of this study is explore the effect of -56T/C(SNP) located in promoter of gamma interferon receptor1 (INFGR1)gene on chronic HBV infection. Methods: Genomic DNA from peripheral blood samples of 150 chronically HBV infected patients and 150 healthy controls was extracted by phenol-chloroform method and DNA analysis and genotyping was performed by PCR-RFLP method. Results: According to obtained genotyping and also statistical analysis, it was observed that between the patients and control group a significant difference existed and the genotypes of TC and CC were high in control group compared to the patients group. Conclusion: The host genetic factors can plays an important role in pathogenesis of HBV infection, Genetic variations in INFGR1 was related to several diseases, in this study we surveyed association between -56T/C (SNP) in INFGR1 and chronic HBV infection, the results of our study showed that presence of C and TC alleles in our population is related to decrease risk susceptibility to chronic infection.