Objective:To observe the effects of ouabain on the proliferation and apoptosis in different leukemia cell lines Jurkat,U937,K562,NB4,HL-60,Raji,and probe the effects of different dosages of ouabain on jurkat cell membrane potential. Methods:Using the MTT method for assaying the inhibition degree of cell proliferation. The morphological changes in leukemia cell lines were observed after wright staining. Cell apoptosis was determined by flow cytometry after Annexin V/PI staining. Jurkat cell membrane potential was labeled by DiBAC4(3)and measured by flow cytometry. Results:MTT assay showed that ouabain could significantly inhibit the proliferation of leukemia cell lines.Wright’s staining and apoptosis detection indicated dramatic proapoptotic morphological changes and enhanced cell apoptosis rate in Jurkat,K562,HL-60 and NB4 cell lines after treatment with ouabain. Cell membrane potential detection showed ouabain didn’t induce the depolarization of Jurkat cell membrane. Conclusion:Ouabain has potent anti-leukemia activity and can significantly inhibit the proliferation and induce apoptosis in leukemia cell lines,meanswhile there were no inhibition effect on the Na,K-ATPase of ouabain.