Abstract: Objective To study the changes of immune cells in HCV-infected patients after stimulation with HCV HVR1 peptide 7. Methods PBMC separated from the blood of HCV-infected patients were cultured with peptide 7,stained with antibodies against IL-10,IFN-γand TNF-α,harvested and analyzed with FACSCalibur software. Results The IFN-γ secreted in CD4⁺CD8^-T,CD4^-CD8⁺T,NK,and NKT cells,was increased in cirrhosis and hepatitis groups.IL-10 secreted in CD4⁺CD8^-T and CD4^-CD8⁺ T cells was increased in cirrhosis group,while IL-10 secreted in NK and NKT cells was decreased in both groups.TNF-αsecreted in NK and NKT cells was increased in both groups. Conclusion Peptide 7 can eliminate virus and alleviate inflammatory reaction by regulating the secretion of cytokines.