Asthma is a complex genetic disease. Genetic and functional characteristics of intcrleukin (IL)-1 support a role as all asthma locus for the IL-1 family on chromosome 2q12-21. This study was performed to investigate the relationship between polymorphisms of IL-1beta promoter region -511C/T and IL-1. receptor antagonist IL-1Ra) gene (IL-RN) and bronchial asthma in Turkish children. Children were divided into two groups: (1) bronchial asthma (n = 328) and (2) healthy control (n = 246). Polymerase chain reaction was used to resolve the IL-1beta -511C/T and the IL-1Ra intron 2 polymorphisms. Plasma IgE concentrations were measured by immunoassays, and skin-prick tests were done in children with atopic diseases. The number of genotype CC and C allele in the control groups in IL-1beta -511C/T polymorphisms increased. The number of genotype 1/1 in the asthma groups and genotypes 112 and 515 and 5 allele in the control groups in IL-1Ra intron 2 gene polymorphism increased. Serum splgE level increased in the 212 genotype in the asthma groups in IL-1Ra intron 2 gene polymorphism. Based oil these results, we conclude that there Was an association of pediatric asthma with the IL-1beta -511C/T and IL-1Ra intron 2 gene polymorphism. Based on these findings, it has been proposed that IL-1beta -511C/T and IL-Ra intron 2 gene polymorphism are useful markers for prediction of asthma.