Abstract: Objective: To investigate the transactivating effect of HCV core protein Methods: A recombinant plasmid containing the encoding gene of HCV core protein was transfected into HepG2 cells and cotransfected HepG2 cells with reporter plasmid pSV lacZ by lipofectamine plus reagents HCV core protein produced in transient expression system was detected at the transcription and translation levels The activity of β galactosidase was detected by a kit,which reflected the transactivating function of HCV core protein Results: The core mRNA and protein can be detected in HepG2 cells lysate which was transfected by the pcDNA3 core The activity of β galactosidase in HepG2 cells transfected by the pcDNA3 core was 5 4 times as higher as that of control plasmid Conclusion: It is suggested that the recombinant plasmid pcDNA3 core can be expressed in HepG2 cell,and it has transactivating effect on SV40.early promoter/enhancer.