Enforced bcl-2 gene expression suppresses apoptosis and confers resistance to anticancer drugs. Here we established a real time fluorescence PCR assay to analyze the association between the bcl-2 gene expression and clinical chemosensitivity in acute myeloid leukemia. Expression levels of the bcl-2 gene were measured and normalized by beta-actin, a housekeeping gene expressed as endogenous reference. By applying real time PCR to clinical samples, we observed that although the bcl-2/beta-actin ratio was not related to FAB subtypes, the changing data following remission induction therapy clearly reflected drug-sensitivity. These results suggest that RT-PCR assay monitored the efficacy of the chemotherapy by quantifying the bcl-2 gene transcript in AML.