Introduction: Phyllodes tumor of the breast (PTB) constitutes 0.2-2% of all breast tumors. The optimal extent of surgical excision (breast conserving surgery or mastectomy) is a matter of debate, especially for cases of borderline and malignant PTBs. From 1995 breast conserving surgery (BCS) is the treatment of choice in all patients with PTB in Cancer Center and Institute of Oncology in Krakow. The purpose of this study is to present experience with BCT patients with PTB at a single institution in Poland. Materials and Methods: Between January 1995 and December 2011, 101 women with PTB were primarily treated surgically at this center. Of these 101 patients, 87 (86.1%) underwent BCS and in 14 (13.9%) patients the mastectomy was performed. This study focused on a group of 87 patients treated with BCS. In 87 patients resection margins were negative. In 82 patients (94.3%) the surgical margin width ranged between 1-2 cm, but in five (5.7%) cases (three malignant and two borderline) it was less than 1 cm (range 0.2-0.9 mm). Those five patients were postoperatively irradiated. Results: In all 87 patients with PTB who were treated with BCS, 83 (95.4%) patients survived five years with no evidence of disease. Two patients (one benign PTB and one borderline PTB) died due to myocardial infarction. In the presented group during five-year follow-up, only two (2.3%) patients died because of malignant PTB (with lung metastases). None of patients developed a local recurrence. Conclusion: The treatment of choice for patients with PTB is BCS. If surgical margin is < 1 cm, adjuvant radiotherapy should be considered.