Autoimmune mechanisms are likely involved in the pathogenesis of idiopathic dilated cardiomyopathy (IDC) and components of MHC may serve as markers for the propensity to develop immune-mediated myocardial damage. This study was conducted to investigate the possible association between HLA-DQA1, -DQB1 alleles and IDC in Han population from northern China by using PCR-based sequence-specific primer (PCR-SSP) technique for HLA genotyping. Among 68 unrelated IDC patients, 4 probands of IDC pedigrees and 100 healthy controls, we found that the alleles of HLA-DQA1*0501 and HLA-DQB1*0303 conferred susceptibility to IDC while HLA-DQA1*0201 and HLA-DQB1*0502, *0504 alleles were in negative association with IDC. The serine at position 57 (SER57) in the exon of HLA-DQB1*0502 and *0504 was confirmed in our experiment as a marker for resistance to IDC. The results suggest that HLA-DQ polymorphism may be involved in the pathogenesis of IDC.