The aim of this study was to investigate the association of single-nucleotide polymorphisms (SNPs) in IL23R with ankylosing spondylitis (AS) in Chinese Han population. Six SNPs were selected for analysis in AS patients and controls. The IL23R mRNA expression was detected using RT-PCR. The differences in the genotypes of rs11209032 and the differences in the genotypes and allele frequencies of rs6677188 between cases and controls were significant. The two SNPs rs11209032 and rs6677188 were in strong linkage disequilibrium. Haplotype analysis noted a higher proportion of GAC in cases and a higher proportion of GTC in controls. The patients with AS showed an elevated level of IL23R mRNA in PBMCs. This study suggested that IL23R polymorphisms were associated with susceptibility to AS in the Chinese population and that IL23R may be involved in the development of AS.