Mixed breast cysts are a breast disease in women of childbearing age, also known as mixed cystic breast hyperplasia. Patients with mixed breast cysts often have swelling and pain in one or both breasts. In mild cases, the pain is like pins and needles, and the pain can be dispersed to the armpits, shoulders and chest and back. Before menstruation, the breasts are obviously swollen and painful, and the pain decreases or disappears after the onset of menstruation, and a small number of patients may also be accompanied by nipple discharge and other symptoms. The course of the disease is sometimes long, but the symptoms often disappear or decrease automatically after menopause. During breast examination, scattered round nodules of varying sizes will be detected, sometimes with tenderness. Adjunctive tests for this disease often rely on breast ultrasonography and mammography. If the test results show a high risk of malignancy of the cysts, and if a tumor cannot be excluded, a puncture biopsy or excisional biopsy can be performed to determine their benignity or malignancy. If the diagnosis of mixed breast cysts is confirmed, it is necessary to be alert to the possibility of malignant changes. Early treatment in accordance with medical advice and active biopsy will help to control the progression of the disease and improve the prognosis.