The TCR Vbeta 24 subfamily genes were amplified in peripheral blood and bone marrow mononuclear cells from 5 cases with acute monocytic leukemia (AML-M(5)) using RT-PCR, to observe the distribution of TCR Vbeta subfamilies. The results indicated that 1 - 19 Vbeta subfamily T cells could be identified in different samples from AML-M(5) cases. The variation of distribution of TCR Vbeta subfamily T cells could be found in different individual samples. The results provided the feature of cell immune function change in skewed distribution of TCR Vbeta subfamily T cells from peripheral blood and bone marrow of patients with AML-M(5).