To observe the effect of Tetrandrine (tet) combined with Droloxifen (DRL) on the expression of bcr/abl mRNA and P(210) BCR/ABL protein of K562 cell line, after K562 cells were cultured in the medium containing Tet (1 micromol/L), DRL (5 micromol/L) separately or in their combination for some time, the changes of bcr/abl mRNA and protein expression were detected by RT-PCR and Western blot respectively. The results showed that the application of single drug of Tet or DRL had no effect on bcr/abl mRNA and BCR/ABL protein expression in K562 cell line. However, Tet in combination with DRL began to downregulate bcr/abl mRNA and P(210) BCR/ABL expression of K562 cells at 48 h and 72 h, respectively. It is concluded that tetrandrine in combination with Droloxifen can downregulate the expression of bcr/abl mRNA and P(210) BCR/ABL protein and the combination may be involved in the mechanism underlying the reverse effects on multidrug resistance in leukemia.