Abstract: Objective This study was to investigate the expression of the fucosyltransferase9 and its clinical significance in human breast carcinoma. Methods FUT9 expression was detected using immunohistochemistry SP method in 11 breast hyperplasia specimens and 114 breast cancer specimens (47 with lymphatic metastasis and 67 without metastasis). Results The positive rate of FUT9 in breast hyperplasia, breast cancer and metastatic lymph node were 9.1%（1/11）,71.9%( 82/114) and 100%（47/47）,respectively. The expression of FUT9 in breast cancer specimens was significantly higher than breast hyperplasia tissues (P<0.01). Breast cancer patients with lymphatic metastasis had higher FUT9 expression rate of 80.9%（38/47）than patients without none lymphatic metastasis 65.7%(44/67). The differences between two groups have statistical significance (P<0.05). We also have found that the expression of FUT9 was positively correlated with TNM staging and the numbers of metastatic lymph nodes in patients (P<0.05）,however the ER status, the PR status and the HER2 status were not associated with FUT9 expression (P>0.05）. Conclusion Expression of FUT9 in breast cancer was positively correlated with malignant progression of disease. Our results strongly suggested that FUT9 may be involved in the process of breast's lymphatic metastasis.