Abstract: Objective To determine the expression level of GATA-2 gene in acute myeloid leukemia with maturation (AML-M2) patients carrying AML1/ETO fusion gene. Methods Bone marrow samples were collected from 23 patients with de novo adult AML-M2 carrying AML1/ETO fusion gene. GATA-2 gene expression was detected by real-time quantitative polymerase chain reaction (RQ-PCR). We analyzed the correlation between GATA-2 gene expression and laboratorial features and clinical prognosis of patients. Results GATA-2 expression levels (GATA-2 gene copies/ reference gene copies) in the patients were found to be 2.17%-1 260.65%. A GATA-2 expression over or equal to 82% was defined as HIGH (10 cases), while an expression level below 82% was defined as LOW (13 cases). No significant differences were found in age, sex, white blood cell count or the rate of bone marrow blasts between HIGH and LOW expression groups (P＞0.05). Although the difference in complete remission rate between the two groups was not statistical significant (P=0.067 8), the HIGH expression group had higher relapse rate (71.43％ vs. 15.38％, P=0.022 3) and higher mortality rate (70.00％ vs. 7.69％, P<0.05). The DFS and OS of the HIGH group are statistically significantly lower than that of the LOW group （P<0.01）. In the HIGH group, the patients choosing HSCT （2/10） are all alive without relapse, while among those choosing chemotherapy only （8/10）, seven out of eight patients died. Conclusion High expression level of GATA-2 in AML-M2 patients with AML1/ETO is associated with high risk of relapse and poor prognosis. Therefore, AML-M2 patients with AML1/ETO fusion gene and high expression of GATA-2 would possibly benefit from additional treatments except for chemotherapy.