Background: Vitiligo is an acquired disorder characterized by the selective destruction of melanocytes, culminating in white macules on the skin. It usually begins at an early age; however, late-onset vitiligo also may occur. The disease burden arising from the psychological effects, especially during childhood, highlights the importance of epidemiological studies of this disease and investigations of differences of disease features between earlyonset and late-onset forms. Methods: A total of 234 vitiligo patients were included in this study and divided into two groups considering the age of onset. The disease characteristics and clinicopathological features of the patients were obtained and compared using written questionnaires. Results: Overall, 25. 6% of patients were early-onset and the mean of age in this group was 18. 86 years compared with 37. 14 years in the late-onset group. The most frequent involvement sites for the early-onset and late-onset groups were the eyelid and hand, respectively. A significant difference was observed between the groups regarding thyroid disorder as a comorbid disease. Conclusion: Marked differences in clinical features were present between patients with early-onset and late-onset vitiligo. Females were more prevalent in the early-onset group and the frequency of thyroid disorder was less relative to the late-onset group. Further studies with different age cut-offs for categorizing early and late-onset vitiligo seem necessary.