Objective To clone and express the E2 gene in envelope region of hepatitis C virus and detect the anti E2 in sera of patients with HCV infection,using the purified E2 Protein.Methods The gene fragment of E2 region was obtained from the sera of patients with HCV infection by random primer reverse transcription and polymerase chain reaction(PCR),and then cloned into procaryotic expression system to express and Purify the protein and detect its antigenicity.Results A segment of E2 region gene with correct code reading frame was obtained,its full length was 984 bp and molecular weight of expressed Protein was 38kD.The detection of the protein performed by ELISA with sera from the patients with HCV infection,testified that it had appropriate antigenicity.Conclusion This experiment can provide the fundamental data for researching on the basic characteristics of HCV envelope protein,nuderstanding the significance of serological diagnosis and designing the anti HCV vassine.