Abstract: Objective: To study the clinical diagnostic methods for breast phyllodes tumors and to determine the principles for clini-cal application of these diagnostic methods. Methods: The clinical and pathological data from 99 cases of breast phyllodes tumors seen in our hospital between May 1999 and July 2007 were retrospectively analyzed.All of these patients were definitively diagnosed with postoperative pathology. Results: The rate of accurate diagnosis before surgery was 29.3% (29/ 99), and the misdiagnosis rate was 70.7% (70/99).We performed mammography in 39 cases, ultrasound in 63 cases, fine needle aspiration cytology in 62 cases, frozen pathology in 63 cases and core needle biopsy in 29 cases.The detection rate was 23.1% (9/39) by mammography, 36.5% (23/63) by ultrasound, 11.3% (7/62) by fine needle aspiration cytology, 77.8% (49/63) by frozen pathology, and 82.8% (24/29) by core needle biopsy.According to the histological criteria of WHO, 26 cases were benign, 61 cases were borderline and 12 cases were malignant.Nineteen cases had local recurrence or metas-tasis after surgery and the recurrence rate was 23.5%.Among the relapsed cases, 3 cases were benign, 11 cases were bor-derline and 5 cases were malignant.In this same group, 8 cases underwent local excision, 8 cases underwent local extend-ed excision, 2 patients underwent simple breast excision and 1 case underwent modified radical mastectomy.The recur-rence rates were 24.2%, 20.5%, 9.0% and 20.0%, respectively, for the aforementioned groups that underwent different surgical procedures. Conclusion: The diagnosis and classification of breast phyllodes tumors depend mainly on histopathological examination.Core needle aspiration biopsy is the best diagnostic method.For suspicious cases, preopera-tive needle aspiration biopsy should be taken to identify the appropriate therapy.Doing so will effectively reduce patient suffering and avoid the possibility of needing a second surgery.