Breast nodules caused by mastitis need to be treated with anti-infective, abscess incision and drainage, or surgical treatment according to the nature of the nodule, and at the same time, be alert to the coexistence of malignant nodules. Breast nodules due to acute mastitis may be hard lumps caused by milk stasis or inflammatory nodules, which can be treated with oral anti-infective therapy such as penicillin and benzathine sodium. Abscesses caused by acute mastitis can also manifest as breast nodules, requiring abscess incision to drain the pus. At the same time, attention should be paid to avoid milk stagnation. Chronic mastitis and plasma cell mastitis can manifest as breast lumps, and the effective treatment is surgical treatment with complete removal of the lesion. If the acute stage is accompanied by infection, it is also necessary to control the inflammation with anti-infection treatment before surgery. It is recommended that the patient consult the doctor in a timely manner, according to the type of mastitis and the nature of the breast nodule to choose the treatment, and pay attention to the differentiation with the breast cancer tumor cells blocking the milk ducts or lymph ducts caused by mastitis, pay attention to follow the doctor’s instructions to improve the examination, so as to avoid delaying the condition.