Acne is common in patients with acne on the face. The causes are related to genetic factors, exuberant secretion of androgen, keratinization of follicular sebaceous gland ducts, and propagation of Propionibacterium acnes. 1. Genetic factors: Parents with a history of acne will significantly increase the chance of acne in the next generation. 2. Excessive secretion of androgens: Excessive secretion of androgens induces a large amount of sebum secretion, which is prone to the formation of acne. 3. Keratinization of follicular sebaceous gland ducts: excessive keratinization of follicular sebaceous gland ducts makes it difficult for sebum keratin plugs to be discharged from the follicle opening, which is also conducive to the formation of acne. 4. Propionibacterium acnes reproduction: the reproduction of Propionibacterium acnes in the hair follicles will form a localized inflammatory reaction, which will also induce acne. There may be other reasons for acne, so it is recommended to go to the hospital in time to have a clear understanding of the cause of the problem and then give targeted treatment or therapy.