Objective:To design the miRNA expression cassettes targeting telomerase reverse transcriptase (hTERT)and to discuss the interfering effect on the expression of hTERT,the telomerase activity and the proliferation of K562,so as to provide a new gene therapy for chronic myeloid leukemia. Methods:miRNA expression cassettes targeting hTERT were constructed and transfected to K562 cells by liposome transfection. The telomerase activity and the expression of hTERT were detected by TRAP-silver staining and qPCR,respectively. Cell apoptosis rate was detected by Annexin V/PI. Results:After 48 h transfection,the expression of hTERT and telomerase activity were significantly reduced. The apoptosis rate of K562 cell was increased. Conclusion:The miRNA expression cassettes targeting hTERT can effectively interfere with the expression of hTERT,inhibit the telomerase activity and induce the apoptosis of K562 cells. RNAi technology based on the miRNA expression cassette is expected to become an efficient tool in molecular level for the treatment of chronic leukemia.