This study was aimed to explore the expression level of angiotensin-II type 1 receptor (AT1) mRNA in bone marrow of myeloid leukemic patients, and its correlation with the proportion of leukemia cells in samples and Hb, WBC, Plt counting in peripheral blood. 51 samples, including 36 AML, 7 CML, and 8 samples of non-malignant hematological diseases as control group were collected. The expression of at1 mRNA was detected by real time-PCR; the expression levels of at1 gene in AML and CML groups were relatively quantitatively analyzed by using 2(-ΔΔCT) and were compared with control group. The results showed that the expression levels of at1 mRNA in AML, CML and control groups were 0.038 ± 0.076, 0.033 ± 0.039, 0.281 ± 0.366, respectively. at1 gene expression in the myeloid leukemic group was significantly lower than that in the control group. The expression level of at1 mRNA in AML was negatively correlated with the proportion of leukemia cells and positively with Hb level in peripheral blood. It is concluded that at1 gene may play a minor role in leukaemogenesis, however, may promote erythropoiesis.