Abstract： Objective To isolate and identify leukemia stem cells from acute myeloid leukemia patients for further research. Methods By Ficoll density gradient centrifugation, mononuclear cells were firstly separated from bone marrow of patients. According to specific surface markers, CD+34 CD+123 of leukemic stem cells were sorted by flow cytometer. Their ability of self-renewal and differentiation were evaluated by colony formation and cobblestone forming ability. At the same time, the purity and cell morphology of CD+34 CD+123 cells was analysed. Results Comparared with total mononuclear cells, the proportion of the CD+34 CD+123 cells after sorting was 10.7 %, and these cells showed the ability of colony forming and cobblestone forming, and the purity proportion of CD+34 CD+123 cells was 62.1%. Conclusion The leukemia stem cells were isolated successfully and could be used in further study.