Background: Vitiligo is very common skin disease resulting from absence of active melanocytes and characterized by focal regions of depigmention, which may induce great psychological problems for the patients. Many therapies such as topical, systemic and phototherapy are not always successful, and re-pigmentation is often incomplete.
Aim of the work: We aimed to compare between the efficacies of topical Khellin 4% and excimer light versus excimer light alone in treatment of vitiligo.   
Patients and methods: A comparative study that was carried out on 100 patients with 200 patches of vitiligo lesions, divided into group I; 100 patches treated with topical khellin 4% solution before excimer light, and group II; 100 patches treated with excimer light alone, for 30 minutes, two sessions per week for six months.   
Results: We found a significant difference decrease in surface area in group I when compared to the surface area in group II. The degree of improvement measured by quartile grading scale in the group I was higher than in group II. Moreover, the improvement rate in group I faster than group II. Topical khellin 4% solution and excimer light, were safe and well tolerated, however, mild erythema and burning sensation were observed and resolved after that.
Conclusion: Topical khellin 4% solution and excimer light, are faster, effective, safe and well tolerated combination in treatment of vitiligo.