Abstract: Objective To investigate the association between signal transducer and activator of transcription 4(STAT4) gene polymorphism and dilated cardiomyopathy (DCM). Methods Two single nucleotide polymorphisms (SNP) (rs7574865 and rs11889341) in STAT4 gene were determined using PCR-RFLP method. The genotype and allele frequencies of these two SNPs were compared between 294 DCM patients and 334 normal controls to test whether SNPs in STAT4 was associated with DCM. Results Compared to healthy controls, the frequency of GG genotype (55.8% in patients vs. 47.9% in controls, P=0.039) and the G allele in rs11889341 (76.4% in patients vs. 70.7% in controls, P=0.023) were significantly increased in DCM patients. We found that increased DCM risk is associated with CC+AC genotypes of rs7574865 (94.2% in patients vs. 89.2% in controls, P=0.025). No significant difference was observed in the distribution of allele frequency in rs7874865 between DCM patients and the controls. Conclusion SNPs in STAT4 gene is associated with DCM. G allele and GG genotype in rs11889341, and CC+AC genotypes in rs7574865, may be associated with signi cantly increased risk of DCM.