Purpose: To investigate the association of labile hemoglobin A1c (LHbA1c) that is formed as a pre-product during synthesis of hemoglobin A1c (HbA1c) with diabetic retinopathy (DR) and HbA1c. Materials and Methods: A total of 91 patients were enrolled in the study which included 32 patients with type II diabetes and DR (group 1), 30 patients with type II diabetes and without DR (group 2) and 29 patients without diabetes and DR (group 3). The patients with DR were subdivided into two groups; those with non-proliferative DR (group 1A:18 patients) and those with proliferative (group 1B:14 patients). Fasting blood glucose, HbA1c and LHbA1c were measured with biochemical analysis and compared statistically between the groups. Results: Mean HbA1c values were 8.9±1.4% (6.5-12.2) in group 1, 7.9±1.7% (5.3-11.9) in group 2 and 4.9±0.2% (4.3-5.2) group 3 (p<0.001). Mean LHbA1c values were 3.1±0.4% (2.1-3.9) in group 1, 2.8±0.5% (2.0-3.8) in group 2 and 1.8±0.1% (1.6-2.0) in group 3 (p<0.001). Mean HbA1c values were 8.2±1.0% (6.5-10.0) in group 1A and 9.5±1.1% (8.2-12.0) in grup1B (p=0.004). Mean LHbA1c values were 2.9±0.4% (2.1-3.4) group 1A and 3.3±0.4% (2.8-3.9) in group 1B (p=0.039). 93.7% of the patients with retinopathy and 63.3% of those without retinopathy had 7.0% and above HbA1c values. 62.5% of the patients with retinopathy and 40% of those without retinopathy had 3.0% and above LHbA1c values. There was a positive correlation between LHbA1c and HbA1c (r=0.87, p<0.001). Conclusion: LHbA1c is associated with diabetic retinopathy and severity of retinopathy likewise HbA1c and as important as HbA1c in control of blood glucose. It seems as an auxiliary parameter which is useful for follow-up of metabolic control of the patients in diabetic retinopathy.