Summary The aim of this study was to investigate the association between the single‐nucleotide polymorphisms (SNPs) of the interleukin 22 (IL‐22) gene and systemic lupus erythematosus (SLE) in a Chinese population. Three IL‐22 SNPs (rs2227485, rs2227513 and rs2227491) were genotyped using SNaPshot SNP genotyping assays and identified by sequencing in 314 SLE patients and 411 healthy controls. The IL‐22 level of serum was assessed by enzyme‐linked immunosorbent assay (ELISA) kits. Data were analysed by spss version 17.0 software. We found that rs2227513 was associated with an increased risk of SLE AG versus AA: adjusted odds ratio (aOR) = 2·24, 95% confidence interval (CI) = 1·22–4·12, P = 0·010; G versus· A: adjusted OR = 2·18, 95% CI = 1·20‐3·97, P = 0·011. Further analysis in patients with SLE showed that the AG genotype and G allele were associated with an increased risk of renal disorder in SLE (G versus A: aOR = 3·09, 95% CI = 1·30–7·33, P = 0·011; AG versus· AA: aOR = 3·25, 95% CI = 1·35–7·85, P = 0·009). In addition, the concentration of IL‐22 was significantly lower in the rs2227513 AG genotype compared with AA genotype (P = 0·028). These results suggest that rs2227513 polymorphism might contribute to SLE susceptibility, probably by decreasing the expression of IL‐22. rs2227513 AG genotype is a risk factor for SLE, probably by decreasing the level of IL‐22. G allele in rs2227513 is associated with increased risk of SLE. AG genotype and G allele in rs2227513 are associated with increased risks of renal disorder in SLE.