Introduction: The renin-angiotensin system (RAS) has been considered to play an important role in the regulation of blood pressure. This study aimed to investigate the correlation between RAS gene polymorphisms and essential hypertension (EH) in the Chinese Yi ethnic group. Materials and methods: A total of 244 EH subjects and 185 normotensive individuals from the Chinese Yi ethnic group were genotyped for AGT M235T (rs699), AT1R A1166C (rs5186), ACE I/D (rs4340) and ACE G2350A (rs4343) polymorphisms by the polymerase chain reaction (PCR)-restriction fragment length polymorphism (RFLP) method. Results: Significant differences in the allele and genotype frequency of ACE G2350A were observed between the EH cases and controls (p=0.001, 0.002). After being grouped by gender, significant differences in the allele and genotype frequency of ACE G2350A and AT1R A1166C were observed between females of the EH cases and controls (ACE G2350A: p=0.000, 0.002; AT1R A1166C: p=0.008, 0.011). After excluding the influence of multifactorial interactions, the ACE G2350A polymorphism is significantly associated with the pathogenesis of EH in the Chinese Yi ethnic group (odds ratio (OR)=1.656, 95% confidence interval (CI) 1.807-2.524, p=0.019). Conclusions: The RAS-related ACE G2350A polymorphism is associated with the pathogenesis of EH in the Chinese Yi ethnic group.