Abstract: AIM：To explore the relationship between gene G9570A polymorphisms of angiotensin-converting enzyme 2 (ACE2) and coronary heart diseases (CHD) among Han population in Northern Anhui Province. METHODS: A total number of 120 patients with CHD and 109 healthy controls were investigated by case-control study. The polymorphisms of ACE2 gene were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). RESULTS: The G allele frequency in male patients with CHD was significantly higher than that in control group (77.6% vs. 60.7%, P<0.05). The GG and AG genotypes in female patients with CHD were slightly higher than those in control group (43.2% vs. 29.5% and 32.1% vs. 28.3% respectively), but no significant difference was found in the frequency of GG and AG genotypes between the female patients and the controls (χ2=0.634, P=0.427; χ2=1.875, P=0.173 respectively). CONCLUSION: The ACE2 gene polymorphism may be associated with coronary heart diseases among male Han population in northern Anhui Province. The male population carrying the G allele runs a higher risk of coronary heart diseases than those carrying other alleles.