Abstract: Objective: To observe the effect of Nrf3 on colorectal cancer LoVo cell line in vitro.Methods: The plasmid was constructed by the insertion of the candidate gene,and was transfected to LoVo cell line.The cell cycle and apoptosis of LoVo cell line were checked by flow cytometry（FCM） in vitro,and the subcellular localization of this candidate gene was observed by the fluorescence microscope.Results: The expression vector pEGFP-N1-Nrf3 was constructed.It expressed in 3 CRC and did not express in paired normal mucosa tissue.Nrf3 was expressed in LoVo cell line and located in cell nucleus.The ratio of LoVo cell in G2/M+S was obviously reduced under the influence of Nrf3 by using FCM,and ratio of LoVo cell in G0/G1 was increased.DNA synthesis and mitosis of LoVo were restrained by Nrf3.The peak of deuto-G1（the peak of apoptosis） was not seen by FCM.So,we thought the apoptosis of LoVo cell line were not influenced by Nrfs in vitro.Conclusion: As a tumor-suppressing gene,Nrf3 has the function of inhibiting cell proliferation of CRC in vitro,but not influence apoptosis.