Occult hepatitis B infection (OBI) is characterized as a form of hepatitis in which detectable amounts of HBV-DNA can be monitored in the peripheral blood of patients whereas the hepatitis B surface antigen is undetectable. The main aim of this study was to investigate whether there is a relationship between OBI and single nucleotide polymorphisms in the -592 region of the IL-10 gene. In this study, the polymorphism at position -592 of the IL-10 promoter of 57 OBI cases was compared and correlated to that of 100 healthy controls by PCR-RFLP techniques. Our results showed that patient and control groups had significant differences regarding genotypes and alleles of the -592 polymorphism in the IL-10 gene. Based on our results, it can be concluded that the -592 polymorphism within the promoter of the IL-10 gene is associated with OBI.