Abstract： Objective To explore whether the expression level of heparanase (HPA) and its coagulation proteins on leukemic blast membrane could determine the hemostatic balance on the surface of leukemia cells.Methods Forty patients of leukemia were studied,and 20 patients with iron dificient anemia as the control group.Expression of tissue factor (TF),heparanase (HPA),tissue factor pathway inhibitor (TFPI),and urokinase plasminogen activator receptor (UPAR) on leukemic blast surfaces were analyzed by flowcytometry.Results The expression of TF,UPAR,and HPA in AML,ALL,CML,CLL and CRAL groups were significantly higher compared with the control group (t =.3.289,3.507,2.701,P ＜0.05; t =2.498,0.802,3.090,P ＜0.05; t =2.642,3.308,2.696,P ＜0.05; t =3.417,3.434,2.382,P ＜0.05; t =2.193,2.272,2.263,P ＜0.05).There were no significantly differences between the leukemic cell expression of TFPI and the control group (P ＞0.05).Expression of TF,UPAR,HPA in AML patients were significantly higher than ALL,CML and CLL groups (t =2.463,2.179,2.276,P ＜0.05; t =2.637,2.402,2.095,P ＜0.05; t =2.548,2.425,2.412,P ＜0.05).The levels of TF,UPAR and HPA in M3,M4 and M5 patients were higher than that of M1,M2 groups (P ＜0.05).There were no significantly differences among M3,M4 and M5 (P ＞0.05).Conclusions These results suggest that TF,UPAR and HPA are predominately expressed on leukemic blast surface,particularly in M3and M4,5 subtypes.The expression of coagulation proteins on blast membrane might determine the hemostatic balance on the surface of leukemia cells.