This study was purposed to investigate the significance of mitosis checkpoint gene chfr expression in acute leukemia (AL). 2 ml of bone marrow were extracted from each of 46 AL patients and 10 normal donors as control and their mononuclear cells were isolated. Then, their chfr expression was detected by using RT-PCR and immunohistochemistry. Normal control blood samples were also analyzed. The results showed that in 15 out of 28 cases of acute non-lymphocytic leukemia and 13 out of 18 cases of acute lymphocytic leukemia expression of chfr gene mRNA and protein significantly decreased as compared with control. The cytogenetic analysis of patients with a decreased Chfr expression revealed abnormal chromosome. In conclusion, Chfr gene is a leukemia-related gene and may play an important role in leukemia pathogenesis.