Objective:To study the clinical pathologic characteristics and differential diagnosis of rare type carcinoma of the breast. Methods:According to the new World Health Organization Classification of Tumors(2003),42 cases of rare type carcinoma of the breast were studied by clinical data and correlated investigation of pathology.Results: All the slides of the breast carcinoma in our department were reviewed,9 cases of glycogen-rich,clear cell carcinoma,4 cases of mucinous carcinoma,2 cases of tubular carcinoma,18 cases of metaplastic carcinoma,6 cases of apocrine carcinoma,1 case of secretary carcinoma,and 2cases of lipid-rich carcinoma were found.Different histologic type has different appearance in the light microscopy,special staining and electromicroscopy.Conclusion:Definite histological classification of breast carcinoma will be helpful in guiding the clinical treatment and estimating patients' prognosis.