Pimples on the corners of the chin and mouth may be due to the presence of acne and may also be caused by folliculitis. 1. Acne: usually associated with a variety of factors, such as genetic factors, high androgen levels, the proliferation of Propionibacterium acnes, sebum overproduction, can make the chin and mouth corners of the area of acne, which is manifested as pimples. 2. Folliculitis: Due to the presence of more hair follicles in the chin and mouth area, improper daily care may lead to bacterial infection of the hair follicles, causing folliculitis, which can also lead to acne in the corner of the mouth, and may be accompanied by itching and redness and other symptoms. If you have acne on the corner of your chin and mouth, and the acne continues to increase, along with other abnormalities, it is recommended that you seek medical attention for examination and treatment.