The causes of a black mark on the face include hyperpigmentation, chloasma, age spots, etc. After clear diagnosis, general treatment, medication and laser treatment can be adopted. 1. Hyperpigmentation: Hyperpigmentation caused by inflammation and trauma will lead to a black mark on the face, patients can apply topical retinoic acid cream and hydroquinone cream to lighten the hyperpigmentation. Laser treatment is also available. 2. Chloasma: Chloasma may be related to endocrine, ultraviolet radiation, heredity and other factors, and it can be treated with topical medication such as 2%~5% hydroquinone cream, 15%~20% azelaic acid cream, and oral vitamin C, vitamin E and tranexamic acid. 3. Age spots: age spots are mainly caused by skin aging and can be treated with liquid nitrogen cryotherapy or laser therapy. There are many reasons why there is a black mark on the face, the above drugs should be used under the guidance of a doctor, it is recommended that patients go to the hospital in a timely manner, after a clear diagnosis of the standardized treatment in accordance with the doctor’s instructions, do not use drugs indiscriminately, so as not to lead to adverse consequences.