Aim: The antioxidant activity of superoxide dismutase (SOD) was evaluated with the duration of neurological problems like poly/sensory neuropathy due to diabetes. Material and Method: The study was conducted with 55 diabetes patients with poly/sensory neuropathy from the out patients endocrinology department of Ramakrishna Mission Sevapratishthan, Kolkata, along with 25 healthy controls. All the procedure of the study was followed with the consent of the participants. In this study, the patients have been selected after nerve conduction velocity (NCV) test for identifying the poly/sensory nerve dysfunction. The SOD activity of the RBC lysate was determined. Result: In our study, the SOD activity was increased with the duration of neurological dysfunction in relation to diabetes. Conclusion: The increase in activity with duration of the diabetic neuropathy may be a result of protective mechanism against oxidative stress developing in the tissue.