Objective: Angiosarcoma of the breast is a rare and heterogeneous entity and its overall incidence is reported as 0.04% of primary breast cancer and as 8% of breast sarcoma approximately. To retrospectively analyze the clinical features and prognosis of breast angiosarcoma, 13 patients were identified by mammary pathologists in Tianjin Medical University Cancer Institute and Hospital from October 1975 to June 2009. Methods:Kaplan-Meier method was carried out to analyze different tumor size, tumor margins and histological grade. Prognosis was tested with univariate analysis by Log-rank test. Results: Median and mean age at diagnosis were 48 years and 44 years, respectively. The duration of follow-up ranged from 7 to 98 months (median, 50 months). All patients underwent surgical excision. Two patients received chemotherapy. Eight patients succumbed to recurrence and distant metastasis. Conclusion:Angiosarcoma of the breast has an exceedingly poor prognosis. The median disease-free survival (DFS) and overall survival (OS) were 28 months and 45 months, respectively. Both tumor size and surgical margins were associated with prognosis (P<0.05). Patients with high histological grade had a tendency of short OS (P>0.05) and a high risk of recurrence and metastasis (P<0.05).