Chin acne may be caused by bad habits, endocrine disorders, folliculitis, sebaceous gland keratinization abnormality and so on. 1. Bad habits: If you eat too much spicy and stimulating food, often stay up late, poor cleaning and other bad habits, it may promote the sebaceous glands secretion of sebum, triggering acne, resulting in the phenomenon of chin acne. 2. Endocrine disorders: when patients have endocrine disorders, it will easily lead to increased secretion of androgens or imbalance of sex hormone levels, causing sebum secretion to be too exuberant, so that the follicle sebaceous gland ducts are blocked, triggering acne and the appearance of constant chin acne. 3. Folliculitis: If the hair follicles on the chin are infected by bacteria or fungi, it will easily cause folliculitis, resulting in acne and may be accompanied by pain. 4. Sebaceous gland keratinization abnormality: If the follicle of the chin sebaceous gland duct keratinization abnormality caused by duct blockage, sebum discharge obstacles, the formation of keratin plugs that is, microcomedones, can appear chin old acne condition. The chin old acne patients exclude bad habits, should go to the regular hospital dermatology consultation and treatment, so as to avoid aggravation of the condition, do not self-medication.