Abstract: Objective : To explore the clinicopathologic features, optimal treatment and prognostic factors of primarybreast lymphoma (PBL). Methods : The clinical records of 37 PBL patients treated in our hospital from 1992 to2006 were retrospectively reviewed. Results : All of the 37 PBL patients were female with an average age of 45years. According to the Ann Arbor stage standard, 16 cases were of stage ⅠE, 12 cases were of stage ⅡE,and 9 cases were of stage Ⅲ E/ⅣE. According to the WHO 2001 lymphoma classification system, all of thecases were B-cell lymphoma (including 26 cases of diffuse large B-cell lymphoma). Of all the patients, 2 un-derwent surgery alone, 21 cases received surgery combined with chemotherapy (14 cases had mastectomyand 9 cases underwent local excision), 8 cases received radiotherapy combined with chemotherapy, and theother 6 cases received chemotherapy alone. The chemotherapy regimen used was CHOP for an average of4-6 cycles. The median follow-up was 36 months (ranging from 1-120 months). The median survival time was53 months. The 3- and 5-year overall survival (OS) rates were 80% and 38%, respectively. No statistical signif-icance was found between patients treated with surgery and those treated with radiotherapy (38.1% and37.5%, P>0.05). A statistical analysis showed that the tumor size and clinical stage at diagnosis were signifi-cant prognostic factors. Conclusion : PBL mostly occurs in women and is almost always found unilaterally. Themain pathological subtype of PBL is diffuse large B-cell lymphoma. Compared with other treatments, radiother-apy combined with chemotherapy is currently the best treatment. Tumor size and clinical stage at diagnosisare the key factors in predicting survival time.