Thrombopoietin(TPO) acts primarily as a megakaryocytic lineage-specific hematopoietic growth factor through a specific cell surface receptor encoded by c-Mpl proto-oncogene. It has been shown successfully to stimulate megakaryocytic development from CD34+ precursor cells, megakmpocytic proliferation and enlargement both in vitro and in vivo. Then, platelet(PLT ) production will be increased. TPO also plays a role in mobilization of erythroid and myeloid progenitor cells. It works with a dose-dependent manner on the PLT number. TPO can reduce the degree and duration of chemotherapy or radiation induced thrombocytopenia both in animals and in human. And it has on effect on platelsts count in volunteer PLT donors and the number of peripheral progenitors transplantation. No severe complications occur during TPO use in clinic trials. So it may be practiced in clinic medicine in the near future, perhaps in treatment of acute leukemia, post-chemotherapy bone marrow inhibition, bone marrow transplantation, transfusion medicine and platelet collection and Storage.