Periodontitis is a multifactorial inflammatory disease. This chronic periodontal disease is caused by a bacterial infection in the gums, which triggers a host inflammatory response. To eliminate the bacterial infection, immune response mechanisms are activated, leading to inflammation and damage to the periodontal tissues. This process involves many cytokines, including IL-6, a cytokine with antibacterial properties. An ongoing bacterial infection in the periodontal tissues leads to its excessive production, which increases inflammation. In this study, we examined IL-6 receptor gene rs1800795 polymorphism in patients with periodontitis in comparison with healthy subjects, as well as the correlation between rs1800795 genotypes and clinical parameters. Additionally we examined the expression of IL-6 in gingival tissue in patients with periodontitis and control subjects, as well as the correlation between gingival expression of IL-6 and clinical parameters. This study included 200 patients with periodontitis and 158 healthy subjects as the control group. Biopsy specimens of gingival tissue in which IL-6 expression was detected were taken from 14 patients with periodontitis and 8 controls who had undergone minor surgery. There were no statistically significant differences in the distribution of IL-6 rs1800795 genotypes and alleles between patients with periodontitis and control subjects. There were also no statistically significant correlations between IL-6 rs1800795 genotypes and clinical parameters in patients with periodontitis. There were no differences in IL-6 expression in the gingival tissue between patients with periodontitis and controls. There was also no correlation between IL-6 expression in the gingival tissue of patients with periodontitis and clinical parameters. In the control group, IL-6 expression in gingival tissue correlated negatively with the approximal plaque index, which reflects the size of bacterial plaques. The results of our study suggest a protective role for IL-6 against bacterial growth in the periodontal tissue. However, it should be noted that several parameters directly or indirectly affect the accumulation of bacterial plaque.