Abstract: Objective：The purpose of this study is to investigate the reversal effects of Vauqueline on human leukemic multidrug resistance(MDR) in K562/A02 cell line MDR1(multidrug resistance 1), MRP(multidrug resistance-associated protein), TopoⅡ(topoisomeraseⅡ), GST-π (glutathione-s-transferase)genes and their proteins. Methods ：The MTT assay was used to analyze the cytotoxic effect of vauqueline. The expression of MDR1, MRP, TopoⅡ, GST-π and their proteins in leukemia K562/A02 cells were respectively detected by semi-quantitative reverse transcription polymerase chain reaction (RT-PCR) and Western Blot. Results ：Semi-quantitative RT-PCR showed that mRNA transcription of MDR1 gene was reduced significantly(P<0.01); and the other genes were not conspicuously changed (P＞0.05).Western blot showed that the expression of P-gp was decreased (P<0.01); the other proteins were not conspicuously changed（P＞0.05）.Vauqueline could increase the accumulation of medicine in K562/A02 cells. Conclusion ：Vauqueline could partly reverse the multidrug resistance of K562/A02 cells.Decreasing of MDR1 gene and p-glycoprotein expression and increase the accumulation of medicine in cells may be the MDR reversal mechanisms in K562/A02 cells.