Café-au-lait macules (CALMs) are a benign epidermal hyperpigmentation disorder with an incidence of 10%-20% in the normal population. Histopathologic examinations have shown increased epidermal melanin without melanocytic proliferation. Lasers are the most effective methods to treat CALMs. The efficacies vary and are influenced by multiple factors. Response rates range from 33%to 96%. Adverse effects may turn up after laser treatment. High recurrence rate is the obstacle that can't ignore and the recurrence rates range from 5%to 50%. The mechanism is still unknown.