Cervical cancer is almost invariably associated with infection by human papillomavirus. It is believed that the host genetic factors such as inflammation-induced cytokines may play a role in cervical carcinogenesis. The IL1B gene, encoding IL-1beta cytokine, contains several single nucleotide polymorphisms. One of them which is in the positions -511 (C-T) related with promoter region has been associated with increased IL-1beta production and with increased risk of developing a number of inflammatory diseases and gastric carcinoma. We assessed the association between the IL1B -511 polymorphism and cervical cancer risk in a hospital-based case-control study among 546 Korean women (182 cases; 364 age-matched controls). The allele frequencies of the case subjects (C, 0.42; T, 0.58) were not significantly different from those of control subjects (C, 0.43; T, 0.57). Control subjects were in Hardy-Weinberg equilibrium. The carriers with -511 C/T or T/T genotypes were at higher risk of cervical cancer with odds ratio of 2.42 (95% CI 1.31-4.46, p<0.005). However, there was no difference of cervical cancer risk between C/T heterologous genotypes and T/T homologous genotypes. In conclusion, in Korean population, IL1B -511 C/C genotypes were significantly associated with a decreased risk of cervical cancer.