Lobular tumor of the breast is a rare breast disease with a lobular structure. It is a fibroepithelial tumor composed of fibrous connective tissue and epithelial tissue of the breast, accounting for 0.3% to 0.9% of breast tumors and 2.5% of fibroepithelial tumors of the breast. It was named cystosarcoma phyllodes tumor (CP) by Dr. Muler in Germany in 1838 based on the morphological characteristics of the tumor, such as fish flesh shape, vesicles inside and lobular division, and has been called by several different names since then. The histologic characteristics of phyllodes tumor are divided into 3 categories: benign, junctional and malignant. The peak incidence of phyllodes tumor in the breast is between 40 and 50 years of age. The main manifestations are painless solitary masses, insidious onset, slow progression, and generally long course. The mass usually does not invade the pectoral muscle and skin, and has good mobility. There is no significant difference in the onset of the tumor between the two sides of the breast. Axillary lymph node metastasis is rare. Some patients have a history of fibroadenoma, and a few have multiple fibroadenomas. The duration of the disease, the size of the mass and its characteristics can vary greatly at the time of consultation. The disease can be divided into two-way growth phase, in which the tumor undergoes a long stabilization period followed by rapid development within a short period of time, and monophasic growth phase, which can be divided into monophasic slow growth type and monophasic rapid type. For lobular breast tumor, the rate of misdiagnosis and missed diagnosis is high in clinical practice. Some auxiliary examinations such as X-ray, ultrasound, infrared and needle aspiration cytology are difficult to diagnose, and the effect of intraoperative rapid freezing method is also unsatisfactory. Hollow-core needle aspiration is currently the most valuable and least invasive examination method for preoperative diagnosis of lobular tumors. Surgical excision is the preferred method for the treatment of lobular tumors of the breast.