Abstract: Objective: To investigate the Clinicopathologic character of the mucinous breast Adencarcinoma and its relationship to prognosis. Methods: 68 patients with the mucinous breast adencarcinoma were analysed retrospectively in the tumor size,the histological type, the lymph node state, the level of ER,PR, NSE. Results: Of the 68 tumors,43 were of the pure type and 25 of mixed type. The rates of ER-positive and PR-positive in the pure type were 88.37% and 79.07%, respectively, and the rates of NSE-positive was 95.35%. The rates of ER-positive and PR-positive in the mixed type were 68% and 56%, respectively, and the rates of NSE-positive was 88%. 5-year survival rate was associated with size of tumor （P＜0.05）, lymph node metastasis （P＜0.05） histological subtype（P＜0.05）. Conclusion: The size of tumor and the lymph node state and histological type are importance factors in the prognosis of the patients with the mucinous breast adencarcinoma. The patients with pure mucinous adencarcinoma had a lower rate of axillary node metastasis and a better prognosis than those of patients with the mixed type mucinous carcinoma.