Objective:To investigate the status of diagnosis and treatment of primary breast cancer in Beijing, 2008.Methods: All the patients who were diagnosed as primary breast cancer in Beijing in 2008 were enrolled in this study. Information of these patients, including the features of tumors, clinical diagnosis and treatment was collected, and filled in the well-designed questionnaire forms by trained surveyors. The missing data were partly complemented through telephone interviews.Results: A total of 3473 Beijing citizens were diagnosed as primary breast cancer (25 patients with synchronal bilateral breast cancer) in Beijing, 2008. Of them 82.09% were symptomatic. 19.02% and 34.11% were diagnosed using fine needle aspiration biopsy (FNAB) and core needle biopsy (CNB), respectively. 15.92% received sentinel lymph node biopsy (SLNB) and 24.27% received breast conserving surgery (BCS). Among 476 cases with Her-2positive, only 96 received anti-Her-2 therapy. We found that the standardization level varied in hospitals of different grades, with higher level in Grade-Ⅲ hospitals. Of note, some breast cancer patients received non-standard primary tumor therapy: 65.63% of the patients with ductal carcinoma in situ (DCIS) received axillary lymph node dissection and 36.88% received chemotherapy; 25.89% of the patients underwent breast conserving surgery without margin status; 12.10% of the patients received chemotherapy less than 4 cycles.Conclusion: Although most breast cancer patients received basic medical care, the mode of diagnosis and treatment should be improved and should be standardized in the future in Beijing.