Abstract: Objective To study the expression of breast cancer stem cell-like markers CD44⁺CD24^-/low in basal-like breast carcinoma(BLBC)and their relation with the prognosis of BLBC.Methods We classified breast carcinomas into 4 groups:luminal A, luminal B/C, Her-2 over-expressing and triple-negative subtype with the expressions of ER, PR and Her-2, respectively.We classified triple-negative subtype into 2 groups:BLBC and normal breast-like group with the expression of CK5/6 and EGFR, respectively.Immunohistochemical(Envision method)was performed to all of the 5 groups, with the selection of antibodies for CD44 and CD24.Results (1)triple-negative group were 60 cases in all, expressed CK5/6 and EGFR in 41cases(68.3%), which was identified as BLBC;low expressed CK5/6 and EGFR in 19 cases(31.7%), which identified as the normal breast-like group.(2)32 cases expressed CD44⁺CD24^-/low phenotype in 41 cases of BLBC78.0%(32/41), compared with luminal A group of 37.9%(11/29), luminal B of25.9%(7/27), Her-2 over-expression group of 17.2%(5/29)and normal breast-like group of 26.3%(5/21)in BLBC(P＜0.05).(3)In all cases of breast cancer which can be evaluated in 145 cases with CD44⁺CD24^-/low immun-phenotype, Ki-67 index was higher and statistically significant(P＜0.05).Conclusion The expression of human breast cancer stem cell markers CD44⁺CD24^-/low in BLBC was significantly higher than other types of breast cancer.Then, we can suppose an association between the prognosis of BLBC and the presence of CD44⁺CD24^-/low cell.