Small white particles around the mouth can be caused by a variety of pathological reasons, including closed mouth acne, sebaceous cysts, perifollicular keratosis, and so on. 1. Closed mouth acne: due to increased androgen levels, bacterial infections, hyperkeratosis of follicular sebaceous gland ducts, and exuberant secretion of sebaceous glands, resulting in keratinized material and sebum clogging and stagnation in the ducts, which manifests itself as small yellowish or off-white pustules. 2. Sebaceous cysts: patients due to daily cleaning is not in place, work and rest disorders, endocrine abnormalities and other reasons lead to a large amount of oil secretion, can not be metabolized in a timely manner, blocking the opening of the follicle sebaceous glands, and then formed scattered granular sebaceous cysts, if secondary bacterial infections can be accompanied by pain. 3. Perifollicular keratosis: due to severe vitamin deficiency or genetic factors, resulting in keratin accumulation around the hair follicle and the appearance of white pimples, containing curly hair, not fused, into chicken skin-like. If the patient’s mouth long white particles, should be timely medical treatment, clear cause, under the guidance of the doctor standardized medication.