Acne vulgaris is also known as acne vulgaris. The exact cause of acne has not been fully clarified, and it is considered to be related to heredity, excessive sebum secretion, androgen levels, abnormal keratinization of follicular sebaceous gland ducts, and proliferation of Propionibacterium acnes. 1. Heredity: Some acne patients have a positive family history of acne, such as parents, grandparents have more acne, affected by genetic factors, the skin may be prone to acne. 2. Excessive sebum secretion: At puberty, hormone levels in the body may change. Under the action of androgens, excessive sebum secretion may cause acne if the follicular opening is blocked. 3. Androgen level: High androgen level will affect the secretion of sebum and lead to excessive sebum secretion. 4. Abnormal keratinization of follicular sebaceous gland ducts: Influenced by certain factors, excessive keratinization of follicular orifices can block the ducts, which can have an impact on the discharge of sebum and shed epithelial cells, and can lead to the formation of acne. 5. Proliferation of Propionibacterium acnes; the onset of acne is related to pathogenic bacteria, such as the proliferation of Propionibacterium acnes to produce inflammatory factors, which can cause an inflammatory response. In addition to this, dietary factors, lifestyle habits, skin care regimen, occupational exposures, diseases, medications, etc., may also lead to the appearance of acne on the skin. It is recommended to go to the dermatology department of the hospital to get a clear diagnosis and then standardize the treatment under the doctor’s guidance.