Microbial plaque that builds up in the gingival crevice area causes inflammation and leads to periodontal disease. Previous research has shown an association between interleukins with periodontitis. The association between interleukin-18 (IL-18) gene polymorphism and periodontitis risk was studied extensively, but the results are contradictory. The aim of this study is to find the association of two IL-18 promoter variants namely -607 C > A (rs1946518) and -137 G > C (rs187238), and the risk of chronic and aggressive periodontal disease by meta-analysis. The databases of PubMed, Medline, Web of Science, and Google Scholar were all explored to find the appropriate studies. The MetaGenyo software was used to calculate each analysis. Outcomes of the pooled analyses revealed significantly elevated risk for periodontitis for both polymorphisms. There is no significant heterogeneity between studies. No significant publication bias was observed. This meta-analysis provided the evidence of a link between IL-18 gene polymorphism in periodontitis.