The treatment of vitiligo is still a challenge. Among various therapeutic modalities, phototherapy with UVB narrowband (UVB-NB) is presently considered a treatment of choice for this skin disease. The exact skin cancer risk deriving from UVB-NB is a serious concern to be determined. We report a case of keratoacanthoma developed in the vitiligo area during a prolonged course of UVB-NB therapy.