Primary breast sarcomas (PBSs) are spectrum heterogeneous sarcomas in breast and the optimal treatment for them is still under discussion. Our study was to investigate clinical characteristics and identify potential prognostic factors for this rare malignancy. The authors retrospectively reviewed 38 patients with PBSs between October 2000 and February 2014 in FuDan University Shanghai Cancer Center. Local control rate and overall survival (OS) were determined by Kaplan-Meier actuarial method. Univariate analysis and Cox proportional hazards model were applied to identify potential prognostic factors. With median follow-up of 40.19 months, 14 patients (14/38) were found with local recurrence. Extensive operation like mastectomy was not superior to local resection (P = 0.167). Three-year recurrence-free survival and OS rate were 61.9% and 89%, respectively. Larger tumor size and local recurrence were indicated as unfavorable prognostic factors in univariate analysis. Cox model identified narrow interval of recurrence free survival as an unfavorable factor (P = 0.048). Surgery remains crucial treatment for PBSs. Mastectomy, however, is not routinely necessary if clear margin could be achieved by local excision. Early recurrence indicates a poor OS.