Pimples around the mouth as well as chin can be caused by acne, folliculitis, sebaceous adenomas, etc. 1. Acne: is a chronic inflammatory skin disease of the sebaceous glands of hair follicles. The pathogenesis of acne is still not fully elucidated, and may be related to heredity, androgen-induced sebum secretion, keratinization of follicular sebaceous gland ducts, and propagation of Propionibacterium acnes. As a result, acne can appear around the mouth and chin. 2. Folliculitis: mainly caused by bacteria, fungi and other pathogenic bacteria, due to the stimulation of inflammation, red pimples around the mouth and chin, i.e. the phenomenon of acne. 3. Sebaceous adenoma: It is a benign tumor characterized by adenoidal differentiation and is associated with sebaceous gland hyperplasia due to abnormal tissue development. It may appear as a spherical papule or nodule around the mouth and chin, i.e., a pimple. In addition, it is recommended that patients with acne around the mouth and chin go to the hospital in time and follow the doctor’s instructions to avoid delaying the condition.