Single-nucleotide polymorphisms (SNPs) in the ETS1 gene are associated with several auto-inflammatory diseases. In this study, we determined whether ETS1 gene polymorphisms confer susceptibility to idiopathic inflammatory myopathies (IIMs) in a northern Chinese Han population. DNA samples were collected from 1017 IIM patients: 363 PM cases and 654 DM cases. The results were compared with those of 1280 healthy controls. Five SNPs in the ETS1 region (rs7117932, rs6590330, rs4937362, rs10893845 and rs1128334) were assessed and genotyped using the Sequenom platform. Our data indicated that the rs7117932 alleles and genotypes are associated with DM and IIMs (P-c = 6.0 x 10(-3) and P-c = 0.029; P-c = 0.013 and P-c = 0.019, respectively). We found a significantly greater percentage of DM and IIM patients with an A allele of rs6590330 than that in the control population (P-c = 0.033 and P-c = 0.013). Additionally, the rs6590330 genotype was associated with IIMs (P-c = 0.020). The percentages of rs7117932 and rs6590330 SNPs were significantly greater in DM and IIM patients with interstitial lung disease (ILD) (all P-c < 0.05). This is the first study to reveal that ETS1 polymorphisms are associated with IIMs alone and IIMs with ILD in a northern Chinese Han population.