As sunlight can cause skin color darkening, many people believe that vitiligo patients should get more sunlight, and even some doctors advise patients to try to sunlight after applying medication. However, recent studies have shown that UV in sunlight not only has components that can increase pigment synthesis, but also has many components that may be harmful to vitiligo patients. The compound UV can cause complex photobiological effects and produce a large amount of ROS, causing skin immune changes and disease development in patients. I also found in my long-term clinical practice that many patients have rapid progression of their disease after sun exposure, and patients who were treated and stabilized in the north in winter went to Sanya and sunbathing for just one day, the white spots spread rapidly. There are also some patients who sunbathe after topical application of bone marrow or compound kalizarin tincture, resulting in skin erythema and blisters. In addition, the vitiligo of exposed areas, due to the lack of skin protection of melanin, is very sensitive to ultraviolet light, long-term high dose exposure may cause the occurrence of skin cancer. To sum up, vitiligo patients should avoid sun exposure.