The causes of chin acne include increased sebaceous gland secretion, abnormal keratinization of sebaceous gland ducts and bacterial infection. 1. Increased secretion of sebaceous glands: If women have endocrine imbalance and increased secretion of sebaceous glands, it may lead to a large amount of oil secretion, which may trigger acne vulgaris on the chin. 2. Abnormal keratinization of sebaceous gland ducts: This may cause the opening of the hair follicle to become narrow or blocked, and the sebum cannot be discharged from the body, and may accumulate in the body, which may lead to acne vulgaris on the chin. 3. Bacterial infection: A common bacterial infection is Propionibacterium acnes, which may cause chin acne if a woman’s body is infected by Propionibacterium acnes. There are many causes of chin acne in women, and it is recommended that patients consult a doctor to clarify the cause of the problem.