Objective To evaluate the efficacy and safety of 308-nm monochromatic excimer light for the treatment of amelanotic nevus.Methods Eighteen patients with amelanotic nevus were treated with 308-nm monochromatic excimer light twice a week for five consecutive weeks.Melanin content index (MCI) was measured in the lesions before and after the treatment.After the final exposure,a three-month follow-up was carried out.Results After the start of treatment,the MCI in lesions increased in a session-dependent manner and approximated to 100％ of that in perilesional normal skin after six sessions of treatment.The follow-up revealed a decrease trend in MCI after the end of the treatment,which was nearly equal to that in perilesional normal skin one month later,and dropped to about 90％ of that three months later.No side effects such as blisters or scar were observed during the treatment.Conclusions The 308-nm monochromatic excimer light is safe and effective for the treatment of amelanotic nevus.Re-exposure to 308-nm monochromatic excimer light after three months is recommended as consolidation therapy.