Abstract： Objective To detect the expression level of DLL4, HES1, VEGF-C, VEGFR-2 mRNA in the bone marrow of leukemia patients and find a new treatment for leukemia with some new principles. Methods 59 patients of leukemia were collected and diagnosed on the basis of clinical manifestations, hemogram, bone marrow morphology, histochemical stain, cytogenetics and flow cytometry. 20 patients with nutritional anemia were chosen as the control group. The bone marrow aspiration were collected. Semiquantitative reverse transcription polymerase chain reaction (RT-PCR) was used to detect the levels of DLL4,HES1, VEGF-C, and VEGFR-2 mRNA. Results The levels of DLJL4, HES1, VEGF-C, VEGFR-2 mRNA in each group with newly diagnosed patients with acute and chronic leukemia were significantly higher than that in the control group (P ＜0.05). The levels of DLL4, HES1, VEGFR-2 mRNA in remission of acute leukemia were significantly higher than that in control group (P =0.041, 0.016, 0.047). In AML group DLL4 and VEGFR-2, HES1 and VEGF-C, mRNA expression were positively correlated (r =0.424, 0.472, P=0.030, 0.014). In CLL group the HES1 and VEGF-C mRNA expression was positively correlated (r =0.997, P =0.042). The levels of VEGF-C mRNA in acute leukemia patients with extramedullary infiltration were higher than that without extramedullary infiltration (P = 0.022). VEGF-C mRNA expression in AML group and the original cell counts were positively correlated (r = 0.315, P = 0.024). Conclusion These results suggested that the interaction of DLL4, HES1 and VECF-C, VEGFR-2 in the pathogenesis of leukemia may promote the development, metastasis and infiltration of leukemia, and these factors in different types of leukemia and extramedullary infiltration are different.