Objective Retrospectively evaluate the sonographic features of different types of mucinous breast carcinoma to improve the preoperative ultrasound diagnostic accuracy rate. Methods Sonographic features of 44 cases of MBC proven by pathological biopsy were analyzed, including the margin,lesion boundary,shape,echo pattern,lesion growth pattern, calcification, posterior acoustic feature,blood flow, lymph node form and data system(BI-RADS)classification for the lesion to sum up the different subtypes of breast ultrasonic ultrasonographic features of mucinous carcinoma. Results 21 cases of pure mucinous carcinoma (PMBC)and 23 cases of mixed mucinous carcinoma(MMBC)were founded. MMBC were more likely to have unclear boundary (73.9%), indistinct or spiculate of margin(73.9%), irregular shape (91.3%), heterogeneous internal echo (87%), more calcification in lesions(52.2%). Lymph node metastasis in MMBC was obviously higher than that of PMBC(P<0.05). Compared with preoperative of the BI-RADS classification and pathological diagnosis, ultrasonography in diagnosing accuracy rate was 68% in malignant lesions, 48.6% in PMBC and 87% in MMBC. Conclusion There are some different ultrasonographic characteristics in different types of breast mucinous carcinoma.MMBC are more likely to have unclear boundary, indistinct or spiculate of margin, irregular shape, more calcification in lesions. On the contrary, PMBC has a circumscribed boundary, abrupt interface edge, rare calcification, rare lymph node metastasis and are easily misdiagnosed as benign lesions. We should pay more attention to avoid misdiagnosis in ultrasonography.