Abstract: Objective To study the expression and the signification of marrow TPO and its receptor c-MPL in acute myeloid leukemia relapse after chemotherapy. Methods The expression of TPO and c-MPL of newly diagnosed acute myeloid leukemia patients before chemotherapy,complete remission after chemotherapy and its relapse was detected by using ELISA and flow cytometry,respectively. Results The expression of bone marrow TPO and c-MPL before chemotherapy was （162.21±39.92）ng/ml and （6.04±4.072）%，it was lower than the （213.19±48.34）ng/ml,（11.23±5.225）% of relapse group siglificantly.The expression of bone marrow TPO and c-MPL before chemotherapy and relapse group were significantly higher than （122.14± 25.75）ng/ml,（2.84±0.724）% of control group.The expression of bone marrow TPO and c-MPL of remission group was （115.82±22.32）ng/ml and （2.81±1.306）%.The expression of marrow TPO and c-MPL between chemotherapied AML patients and normal group was no significant difference(P>0.05).The expression of bone marrow TPO was positively correlated with c-MPL. Conclusion （1）The high expression of bone marrow TPO and its receptor c-MPL may be associated with the relapse of acute myeloid leukemia after treatment.（2） The expression of bone marrow TPO and c-MPL was significantly higher in relapse group than before chemotherapy.It suggested that TPO/c-MPL signaling pathway may play an important role in acute myeloid leukemia relapse and refractory after treatment.