Abstract: Objective To study the expression levels and its clinical significance of angiopoietin 2 (Ang-2) gene in acute lymphatic leukemia(ALL). Methods The qualitative detection method was established with SYBR Green Ⅰ by real-time fluorescent quantitative PCR, and Ang-2 mRNA was measured in 51 cases of pre-therapeutic ALL. In addition, the expression of Ang-2 gene was also analyzed in 20 cases of non-malignant hematological diseases. Results The expression of Ang-2 gene was found in all the patients, and Ang-2 expression level in ALL patients was significantly higher than that of the controls (P<0.05). No significant relationship was found between Ang-2 expression level and clinical characteristics (age, haematogloblin, WBC count, platelet count, LDH, blast cells in peripheral blood, blast cells in bone marrow). The expression level of Ang-2 have no effect on one year replase rate and survival rate in ALL. Conclusion Ang-2 expression level in ALL patients was higher than that in non-malignant hematological diseases, and there may be no relationship with clinical manifestation, treatment and prognosis.