The current study was designed to investigate the relationship between the expression of CD44V6 in the blood, cancer tissues and lymph node in the patients with breast cancer and chemotherapy.The expression of CD44V6 in breast cancer tissue was examined by immunohistochem. and that in circulating lymphocyte and lymph node adherence cell by flow cytometry.CD44V6 level was increased in cancer tissue (t=4.71, P<0.05) and the metastatic lymph node (t=5.11, P<0.05), but no change in circulating lymphocyte (t=0.98, P>0.05).CD44V6 expressed in tumor cells was strong pos. and pos. rate was 100 %.The expression of CD44V6 in benign tumor tissue was neg.After chemotherapy with CMF, CD44V6 expressed in tumor cells was still 100 %.CD44V6 level was decrease, but no change in blood and lymph node comparing with before chemotherapy.It was proved that the expression of CD44V6 was closely related with the metastasis to lymph node and more closely related to the prognosis of breast cancer.Meantime, chemotherapy could inhibit the increase of CD44V6 by its cytotoxicity effect and could inhibit metastasis in certain extent.CD44V6 was found to be a useful marker for the metastasis to lymph node in breast cancer.