Abstract: Objective:To investigate the outcome of breast cancer patients with potentially malignant calcification receiving breast-conserving surgery, as well as the results of patients in different age levels. Methods:This retrospective study reviewed the medical re -cords of 436 patients who underwent breast- conserving surgery in Tianjin Medical University Cancer Institute and Hospital between January 2005and December 2008. Of the 436 patients, 122 were assigned as the calcification group because they had potentially ma -lignant calcification on mammography, whereas the remaining 314 patients were assigned as the control group. Patients were classi -fied into three subgroups based on their ages, namely, young-aged subgroup (aged ≤ 35years old), middle-aged subgroup (aged36- 55 years old), and old- aged subgroup (aged > 55years old). Results: Potentially malignant calcification on mammography is a significant prognosis factor of locoregional recurrence- free survival (LRFS) and overall survival (OS). In the young- aged patients, a higher inci-dence of positive events (relapse, metastasis, and death) was observed in the calcification group. The outcomes of patients with poten-tially malignant calcification on mammography were worse than those without in the middle-aged subgroup. No significant difference in LRFS and OS was observed in the old-aged patients between the calcification and control groups. Conclusion: Potentially malignant calcification on mammography was an independent prognosis factor of LRFS and OS in breast cancer patients receiving breast-conserving surgery. In the old-aged patients with breast cancer, potentially malignant calcification on mammography should not be regarded as a contraindication to breast-conserving surgery.