BACKGROUND: Diabetic peripheral neuropathy (DPN) is the dysfunction of peripheral nerves attributed to chronic hyperglycemia after excluding other causes. Vitamin B12 deficiency is a potential comorbidity that is often overlooked in diabetic patients. Potentially reversible vitamin B12 deficiency induced neuropathy may be inappropriately labelled as diabetic peripheral neuropathy. METHOD: 162 cases were included over a period of 1 year. After a detailed history and examination, severity of peripheral neuropathy was assessed by Toronto Clinical Scoring System. Presence of DPN was confirmed by Nerve Conduction Study. Vitamin B12 estimation was done by ELISA technique. RESULT: DPN was found in 35.18% of patients. Longer duration of diabetes, poor glycemic control, higher daily dose and duration of metformin use, height of patients, low HDL were found to be risk factors. 25(15.43%) out of 162 and 10 (17.5%) of patients with DPN were vitamin B12 deficient. Mean vitamin B12 in patients with DPN was 460.09 ± 264.07 pg/ml which is significantly lower than those without DPN (580. 27 ± 255.31 pg/ml; p<0.01). CONCLUSION: Vitamin B12 deficiency is found to be a potential comorbidity in type 2 diabetes mellitus patients and hence regular monitoring of its serum levels and supplementation must be considered especially in the patients on metformin therapy.