Objective：To explore the effects of Bmi-1-siRNA on human esophageal EC9706 cells. Methods：Different concentrations of Bmi-1-siRNA（50，100，150 nmol/L） was used to transfect EC9706 with different time exposures（24，48，72 h）. Changes of cell cycle in EC9706 cells before and after the transfection were detected by MTT. Levels of protein of Bmi-1，telomerase reverse transcrip－tase（hTERT），P16 in transfected cells were measured by immunocytochemistry. Levels of Bmi-1mRNA in transfected cells were measured by situ hybridization. Results：Bmi-1-siRNA effectively inhibited cell proliferation of EC9706 cells in a dose and time dependent way（F=1.322，2.881；P<0.001）. Expression of Bmi-1 and hTERT protein was decreased and that of P16 was increased（F=12.229，23.556，19.414；P<0.001）. Conclusions：RNAi of Bmi-1 in EC9706 cell line could effectively inhibit EC9706 cell proliferation，whose mechanism may relate with down-regulation of Bmi-1 mRNA，Bmi-1，hTERT protein expression and up-regulation of P16 protein expression.