Abstract: Objective To study the effects of tetramethylphylpyrazine(TMP)on cell proliferation and reversing drug resistance in human lung adenocarcinoma cell line AGZY.Methods The drug sensitivity of AGZY cells to ADM was measured by MTT assay.The cell proliferation states were investigate by cell growth curve and cell colony formation test.The migration and invasion of AGZY cells were measured with cell invasion assay.The protein expression levels of nm23 and MDR1 were determined by western blot analyses.Results The IC₅₀ and drug-resistant index of ADM were decreased by TMP.Cell proliferation ability was decreased obviously.Cell invasion ability was decreased.The expression of nm23 was upregulated, and the expression of MDR1 was downregulated.Conclusion TMP could inhibit the growth of AGZY cell.TMP could enhance the AGZY cell chemosensitivity to ADM, and it maybe related with the down-regulation of MDR1.TMP can restrain AGZY cell invasion and metastasis, and it may have relationship with the upregulation of nm23.