[en] Objective: To realize the role of tyrosine phosphatase in the radiation injury of hematopoietic cells (HCs) and to deepen the understanding of the mechanism of radiation injury on HCs. Methods: The effects of tyrosine phosphatase inhibitor per-vanadate on the G-CSF induced growth responsiveness in irradiated and unirradiated NFS-60 cells were observed by MTT method. Results: It was showed that the influence of per-vanadate on cell growth was dependent on the concentration of G-CSF in the medium:under the condition of lower G-CSF concentrations cell growth could be improved by administration of per-vanadate in certain doses;on the contrary,administration of per-vanadate could inhibit cell proliferation when the concentration of G-CSF was high enough. Compared with unirradiated cells. per-vanadate could more strongly promote cell growth and relatively weakly inhibit cell proliferation in 3Gy-irradiated NFS-60 cells. Conclusion: The results suggest that tyrosine phosphatase in the cells might take part in regulation of cell growth and irradiation could enhance the effect of tyrosine phosphatase to inhibit cell growth