Small bumps on the side of the nipple can be seen in Montgomery’s nodes, sebaceous cysts, sebaceous glanditis or mastitis, or breast cancer, as follows: 1. Montgomery’s nodes: normal structure, usually closed, will be raised when stimulated, and will open during lactation and pregnancy under the influence of hormones, patients do not need to worry; 2. sebaceous cysts: sebaceous glands are contaminated, not cleaned in time and blocked to form cysts. Patients should clean their breasts daily and change clean and comfortable underwear. If it does not disappear for a long time, the patient needs to have it surgically removed; 3. Seborrhea or mastitis: a rash can appear due to bacterial infection of the breast tissue or sebaceous tissue caused by skin breakage. Patients need to take anti-inflammatory drugs, eat more fruits and vegetables, and eat less spicy and stimulating food; 4. Breast cancer: the patient’s skin will be like orange peel bumpy and should be treated in time.