Background: Cataract is a major cause of blindness. Diabetes mellitus is a major risk factor for the development of cataract. Diabetic patients have 25 times higher risk of cataract than non-diabetic population. The metabolic changes accompanying hyperglycemia is increased activity of the polyol pathway and aldose reductase (AR) is a key enzyme of polyol pathway. Aldose reductase is responsible for generation of more oxidative stress by decreasing GSH in diabetic patients which is thought to be a major factor to initiate the process of cataractogenesis. The present study was designed to determine significance of aldose reductase diabetic cataract and its correlation with reduced glutathione (GSH) and Malondialdehyde (MDA) in diabetic cataract patients. Methods: In this study we measured MDA as oxidative stress marker andGlycated Hb (HbA1c) glycemic index marker levels of GSH and AR in erythrocytes of Type2 diabetic cataract patients (n = 30) and non diabetic senile cataract patients (n=30) compared with age matched normal controls(n=30). Results: We found increased levels of AR, HbA1c and MDA, and decreased levels of GSH in diabetic cataract patients compared to non diabetic senile cataract patients and normal controls. Conclusions: From the result it is concluded that AR play a major role in generation of more oxidative stress in diabetic patients which may be the cause of early cataractogenesis in diabetic patients as compared to non diabetic senile cataract patients.