Objective: Hypertensive retinopathy is an important complication and a major site of target organ damage from hypertension. Angiotensin converting enzyme (ACE) has a main role in cardiovascular physiology. It was shown that ACE gene polymorphism is related to plasma concentrations of ACE. We aimed to investigate the relationship between ACE gene polymorphism and hypertensive retinopathy. Methods: One-hundred and eight patients (62 female, mean age; 52.8 ± 7.0 years) with essential hypertension and 30 healthy volunteers were enrolled in this study. Hypertensive retinopathy was diagnosed in a dark room with direct ophthalmoscopy by a single ophthalmologist who was blinded to clinical data. Polymerase chain reaction analysis was used to detect the insertion/deletion (l/D) polymorphism of the ACE gene. Patients were assigned to Group DD, Group ID and Group II. Three genotypic subgroups were compared for hypertensive retinopathy. Results: There were 42 patients (27 female, mean age: 52.4 ± 7.8) in DD group; 51 patients (28 female, mean age: 53.6 ± 6.9) in ID group and 15 patients (7 female, mean age: 51.2 ± 5.6) in II group. Basal characteristics of the patients were similar in the three groups. The genotypic distributions of patients and healthy controls were comparable. Hypertensive retinopathy was determined in 15 (35.7%) patients in DD group, 8 (15.6%) patients in ID group and 2 (13.3%) patients in II group (p < 0.05). Conclusion: We found a significant relationship between ACE gene I/D polymorphism and hypertensive retinopathy. Identification of ACE genotype in hypertensive patients might be useful to discriminate the patients who are more susceptible to hypertensive retinopathy.