objective At present, most operable breast cancers are confirmed by excision biopsy during the operation. If the breast cancer was definitely diagnosed by Fine -Needle Aspiration cytology(FNA) preoperatively, the excision biopsy could be avoid. Methods We diagnosed 118 inpatients of breast mass with physical examination and FNA from September, 1995 to May, 1996. Results The sensitivity and positive predict value of FNA for diagnosing breast cancer are 95.7% and 97.1%. When the palpation and FNA are both positive, the doublepositive predict value for breast cancer is 100% in our study. It is the indication of using FNA that a breast mass was diagnosed as cancer by physical examination. We can treat a breast mass with redical operation directly without excision biopsy, if the breast mass was confirmed as breast cancer by both physical examination and FNA. Conclusion We concluded that the preoperative FNA could partially replace the excision biopsy for confirming breast cancer.