Abstract: Objective To construct Retrovirus-mediated shRNA expression vector targeting bmi-1,which could transfect LoVo cells so as to establish stable LoVo cell line and to investigate the effect of stable expression bmi-1shRNA in LoVo cells,paving the way for further application in RNAi gene therapy. Methods According to the principles of RNA interference technology,we designed and constructed the complementary oligonucleotides encoding hairpin RNA which specifically targets bmi-1 gene.The nonsense oligonucleotides were also designed and constructed.Then,we transfected them into colon cancer LoVo cells by lipofectamineTM 2000.After screening culture by puromycin,stable transfected LoVo cell line was established.We observed the proliferationchange of stable transfected LoVo cell line after the inhibition of bmi-1 by microscope,MTT,fluorescence quantitative PCR and Western blot. Results The vectors expressing shRNA targeting bmi-1 was constructed successfully.Stable transfected LoVo cell line was established.The rate of inhibition on bmi-1 mRNA is 80% and the rate of suppression on bmi-1 protein is 82%（P<0.05）. Conclusion The vectors expressing shRNA targeting bmi-1 can inhibit cellular proliferation and bmi-1 gene expression,but the vectors had no obvious affects on cell morphology.