Acne under the mouth can be treated by general treatment, medication and fruit acid peeling. 1. General treatment: choose water or suitable cleansing products to remove excess oil, dander and bacterial mixture on the skin surface, but not over-washing, pay attention to oil control and moisturizing, and use mild moisturizing milk externally. Avoid squeezing and scratching the lesions with hands. Limit the intake of high glycemic index foods and milk that may trigger or aggravate acne, keep bowel movement smooth, and avoid staying up late at night. 2. Medication: Benzoyl peroxide, azelaic acid cream and other drugs can be used externally, which can kill Propionibacterium acnes and dissolve acne. Minocycline, isotretinoin and other drugs can also be taken orally. 3. Fruit acid peeling: It is to promote the shedding of old stratum corneum and the proliferation of skin elastic fibers through a high concentration of fruit acid, so as to improve the condition of the skin and promote the shedding of acne. All of the above drugs should be used under the guidance of a doctor, and it is recommended to go to a regular hospital for treatment.