Acne is usually referred to as acne. Acne on the side of the face is usually related to androgen-induced sebum secretion, Propionibacterium acnes reproduction, or keratinization of follicular sebaceous gland ducts. 1. Androgen-induced sebum secretion: Follicular sebaceous glands, as independent endocrine tissues of the skin, are regulated by sex hormones. Increased androgen levels or imbalance between male and female hormone levels after puberty can cause sebaceous glands to enlarge and sebum secretion to increase. Increased androgen levels due to polycystic ovary syndrome may also cause acne on the side of the face. 2. Propionibacterium acnes: Sebum provides oil and an anaerobic environment for the growth of microorganisms such as Propionibacterium acnes in the hair follicles, which can multiply in the hair follicles, resulting in inflammation and the formation of acne. 3. Keratinization of the sebaceous gland ducts of the hair follicles: When the keratinocytes in the ducts of the hair follicles proliferate and keratinize excessively, the latter causes sebum excretion to be blocked, and acne is formed when sebum and keratin plugs accumulate at the mouth of the hair follicles. Acne on the side of the face may also have other causes, you can go to the hospital specialist consultation, timely identification of the cause of the disease, follow the doctor’s instructions for treatment, avoid squeezing acne, in order to prevent scarring.