The common causes of pain in a circle around the nipple include breast hyperplasia, trauma, acute mastitis, inflammatory breast cancer and so on. 1. Breast hyperplasia: It usually worsens before menstruation and is closely related to emotional changes, exertion and other factors. During the period of breast hyperplasia, it can lead to increased sensitivity of the surface nerves in and around the nipple, which in turn can cause local discomfort and result in a painful sensation in and around the nipple. 2. Trauma: If the area around the nipple is damaged by the outside world, it can cause pain, and it is also easy to be invaded by bacteria, resulting in local inflammation, redness, swelling, heat and pain. 3. Acute mastitis: usually caused by milk stasis combined with Staphylococcus aureus infection, resulting in localized hard lumps in the breast, and a tingling sensation, burning sensation. So it can also cause a circle of pain around the nipple. It mostly occurs in breastfeeding women and is generally more common unilaterally. 4. Inflammatory breast cancer: it is a kind of highly invasive invasive breast cancer with rapid development and poor prognosis. Patients usually show the symptoms of red rash and pain in the skin of nipple and areola. Therefore, it can also cause a circle of pain around the nipple. Therefore, if there is a circle of pain around the nipple, it is recommended to consult a doctor as soon as possible for a clear diagnosis and symptomatic treatment, so as not to delay the condition.