The causes of uneven skin tone in patients, consider the following aspects: 1, congenital genetic factors: congenital genetic factors cause uneven skin tone. 2, improper skin care: excessive cleaning causes local dehydration of the skin, and after dehydration the skin barrier is damaged, resulting in uneven distribution of skin pigment. 3, sunburn: ultraviolet light has a great affinity for human melanocytes, especially in different seasons have different Affinity, especially in summer, UV radiation is stronger, causing the skin to produce a large number of melanin particles, appearing skin color deepening, resulting in uneven skin tone. 4, long-term high sugar diet: due to the conversion of sugar into lipids, the skin secretion of oil increases, appearing oil and water incompatibility, therefore also appearing uneven skin tone. 5, skin pigment metabolism disorders: such as common melanosis, chloasma, nevus of Ota . 6.Phototherapy: pigmentation after causing inflammation will also appear uneven skin tone. Therefore, for uneven skin tone, patients are advised to go to regular hospitals and seek treatment from qualified dermatologists.