To clarify the relationship between angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and diabetic retinopathy in type 2 diabetic patients by meta analysis. 16 eligible articles were selected in this study, including 1 014 patients with diabetic retinopathy and 1 135 controls. The meta analysis revealed that systematic data Z= 2.91 ( P = 0.004 ), OR = 1.69 ( 95% CI 1.19-2.40). There is association between ACE gene I/D polymorphism and the diabetic retinopathy in type 2 diabetic patients.