Most of the clinically treatable spots are chloasma, which is related to endocrine factors, sun exposure and external environmental stimulation. From the viewpoint of pathogenic factors, sun exposure is one of the pathogenic factors. Long-wave ultraviolet rays in the sun irradiate the skin, which can cause pigment increase and melasma color deepen. Therefore, it is best to remove spots in the weaker sunlight season, preferably in autumn and winter. The commonly used clinical methods to remove melasma include laser, medication and fruit acid brushing, among which laser and fruit acid are suitable for stable melasma. After laser and fruit acid resurfacing treatment, the skin of melasma area may be red and swollen, so strict sun protection is needed. Because ultraviolet rays are weaker in autumn and winter, the effect of ultraviolet rays on the skin of the treated area is weaker after sun protection, and the effect achieved is better. Drug spot removal also needs to avoid sunlight, so the effect of spot removal is better in autumn and winter.