Abstract Background: Vitiligo is an acquired depigmenting cuta-neous disorder characterized by the loss of melanocytes from the epidermis. It affects approximately 0.5% of the population worldwide. Aim of Study: To determine serum vitamin B 12 level in patients with vitiligo and healthy controls to determine its possible role as a disease biomarker. Patients and Methods: This study was conducted on 40 patients with vitiligo and 40 age and sex matched healthy controls recruited from El-Demerdash Hospital, Ain Shams University. Results: Serum level of vitamin B12 decreased in cases in comparison to control, and there is an inverse relation between vitamin B 12 and affected body parts. Conclusion: This study confirms that vitamin B12 is a very efficient and simple biomarker for vitiligo cases. Thus we recommended the use of vitamin B 12 in investigation to improve our diagnostic capabilities in vitiligo patients.