There are many reasons why one breast is large and one is small, and the specific treatment varies: 1. congenital breast size is not the same, breast implant augmentation can be performed. 2. enlarged lymph nodes, due to the stimulation of lymph nodes, swelling painful performance, resulting in two breasts of different sizes. The lymph nodes need to be removed surgically after anti-inflammatory treatment to control the growth of the lymph nodes. 3. Breast enlargement, under the influence of estrogen, the hard lumps of breast enlargement will appear swollen and painful, if it seriously affects life and aesthetics, the hard lumps can be removed surgically. 4. Breast fibroids, patients will show rapid enlargement of the lumps during pregnancy and lactation, the lumps need to be removed before pregnancy and the envelope needs to be removed. 5. Breast cancer. Patients will have lumps and orange peel-like changes in the breast. Early detection requires surgical excision and late detection requires chemotherapy.