To explore CD34(+) antigen expression in new diagnosed acute myeloid leukemia (AML) and analyze the prognosis for CD34(+) AML patients, the expression of antigen CD34 in 238 AML patients was detected by indirect immunofluorescence assay. The results showed that CD34 in 92 out of the 238 patients (38.7%) were positive, there was relationship between the CD34(+) expression and FAB subtypes (M(0), M(1)), and no CD34(+) expression was observed in M(3) subtypes. The complete remission rate of CD34(+) AML patients was 32%, which was lower than that of CD34(-) AML (61%). The lymphoid-associated antigen (CD7) was significantly increased in CD34(+) AML patients, compared with CD34(-) patients (P < 0.05). It is concluded that CD34(+) AML patients show poor prognosis and lower CR rate. The detection of CD34 expression is of some value in predicting prognosis in AML.