Background: Vitiligo is an acquired epidermal pigment loss of the skin. Oxidative stress is one of the major theories in the pathophysiology of vitiligo. FOXO1 is the forkhead members of the class O (FOXO1) transcription factors, and plays an important role in cell cycle regulation, apoptosis, oxidative stress, and DNA repair. Aim of the Work: to detect the level of FOXO1 in patients with vitiligo. Subjects and Methods: Fifty patients with Vitiligo were included in the study, and fifty healthy controls matched in age and gender to Vitiligo cases. All participants were subjected to full clinical and laboratory investigations. Blood samples had been taken from all studied participants (Vitiligo cases and healthy controls) to study serum level of FOXO1 and its relationship with the pathogenesis of vitiligo. Results: Serum level of FOXO1 was significantly higher in Vitiligo patients as compared with healthy controls, serum level of FOXO1 was slightly higher in female's Vitiligo serum as compared with males; but with no statistically significant difference, serum level of FOXO1 was slightly higher in Vitiligo serum among patients with positive as compared with negative family history but with no statistically significant difference. There was non-statistically significant linear correlation between serum level of FOXO1 and patients' age, disease duration and last new lesion, however, there was a statistically significant positive linear correlation between serum level of FOXO1 and Vitiligo Area Scoring Index (VASI) in studied Vitiligo patients. Conclusion: We can conclude that, FOXO1 might be associated with susceptibility to vitiligo, especially active vitiligo, and that increased FOXO1 levels in vitiligo patients might be associated with oxidative stress.