Allergic rhinitis is a chronic inflammatory disease with a genetic background, and IL-18 (formerly IFN-γ-inducing factor) is a well-known pro-inflammatory cytokine. The aim of this study was to investigate whether the IL-18/-607 promoter polymorphisms were associated with allergic rhinitis in the Korean population.Prospective study.Deoxyribonucleic acid was obtained from the blood samples of 160 Korean children with allergic rhinitis and from 166 healthy controls. The IL-18/-607 polymorphism was analyzed by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) analysis.The frequency of the AC genotype of the IL-18/-607 gene polymorphism was significantly greater in allergic rhinitis patients than in controls (P<0.05).The A allele in the IL-18/-607 gene promoter region may be involved in the development of allergic rhinitis in the Korean population.