Abstract: Objective To investigate the clinical characteristics and prognostic factors of the patients with breast cancer who had symptomatic malignant pleural effusion (MPE). Methods The data of 36 patients underwent pleurodesis for malignant pleural from Nov 2008 to Dec 2010 were collected. It included the patients' general clinical data (age, ECOG, surgical-pathological staging, postoperative DFS, the pleural effusion being the first recurrence,first-line chemotherapy, other effusion, and bilateral pleural effusion), details of pleural effusion (whether it was congestive pleural effusion, number of the effusion cells or not, number of monocytes, LDH, CEA, CA153, CA125, protein, and quantity of pleural effusion) and treatments of pleural effusion (local treatment, local chemotherapeutics, whether to use IL-2). The factors which influenced pleural effusion treatments and its time control under the above conditions were analyzed. Results The median time of the interval between surgery and the onset of MPE was 44 months(0-180 months). The patients with the interval time between surgery and onset of MPE longer than 44 months had higher response rate(66.7%) than those less than 44 months (33.3%)（P=0.046）.The patients receiving first line chemotherapy (65.0%) had higher response rate than those receiving more than first line chemotherapy (31.3%,P=0.044）.The mononuclear cell number in the pleural effusion influenced the response rate to a significant degree（P=0.046）. The median pleural effusion control time was 4 months.The patients with lactate dehydrogenase (LDH) concentration higher than 400 u/L(6 months) had longer median pleural effusion control time than those with LDH concentration lower than 400 u/L (2 months)(P=0.032). Conclusion Malignant pleural effusion was the common presentation for advanced breast cancer. The interval time between surgery and onset of MPE, first line chemotherapy and mononuclear cell number in the pleural effusion significantly affected the response rate.The LDH concentration in pleural effusion was a good predictor of pleural effusion control time.