Objective To investigate the correlation of prognosis with the immunophenotype in acute myeloid leukemia(AML)patients.Methods Immunophenotyping was performed in 131 patients with AML by mtdtieolor flow cytometry.Correlation of immunophenotype with other laboratory parameters such as initial white blood cell count(WBC),platelet count(PLT),hemoglobin(Hb),and the complete remission(CR)ratio was analyzed.Results In these AML patients,myeloid antigens CDl3,CD33 and myeloperoxidase(MPO)were more highly expressed than other antigens.Expression of CD34 and HLA-DR were lower in acute promyelocytic leukemia(M3)subtype.The expression of lymphocyte antigen CD19 and CD7 were the highest.CD7 expression was associated with age(t=-2.27,P＜0.05).CD14 was associated with initial WBC(Z=-2.284,P＜0.05).The overall CR ratio was 56.5%among all patients.CD34positive patients had a significantly lower CR rato(45.1%),compared with the CD34 negative patients whose CR ratio was 75.6%(x2=11.524,P=0.001).The CR ratio was significantly lower in cases expressing both CD34 and HLA-DR(74 patients with CR rate 41.9%)than in cases expressing only CD34 or HLA-DR(38 patients with CR rate 78.9%)and both negative(19 patients with CR rate 68.4%)(Z=-3.492,P＜0.01).However,other antigens,including CD7,CD19,CD13,CD33,CD38,CD15,CD64,CD14 and MPO had no significant association with CR ratio.Logistic regression analysis showed that age(60 years or older),initial WBC(more than 50 x 109/L),PLT(more than 30 x 109/L),Hb(less than 60g/L)and CD34 were independent adverse factors for achieving CR.Conclusions In AML patients,age,initial WBC,PLT,Hb and CD34 are associated with CR ratio.Detection of immunophenotype may help to estimate prognosis of patients with AML and guide the treatment of AML.