Freckle is a very common pigmented disease in dermatology, its incidence is very high in clinic, and the main involved population is female. The causes of this disease: 1, genetic factors: because this disease is an autosomal dominant disease, many patients have freckles in their families, only some of them have light clinical manifestations, some of them have heavier clinical manifestations. 2, sun exposure factors: freckles are also affected by sun exposure, especially ultraviolet rays in sunlight, so the color of freckles is usually heavier in summer, and the color in winter is relatively lighter. The treatment methods for this disease are more and more effective. At present, the main method is to solve the problem by using q laser or intense pulse light, and the effect is very good.