Abstract： AIM:To explore the natural consequence of acute hepatitis E and chang of immune state. METHODS:The serum levels of IFN-γ, IL-4 and IL-12 were measured by using enzymelinked immumo sorbent assay, and T lymphocyte subsets of peripheral blood were observed by fluorescence activated cell sorting(FACS). RESULTS:Compared with the normal people,groups of Anti-HEV IgM seroconversion patients with acute hepatitis E infection had a significant increase of IL-12, IFN-γ, IL-4,Th1/Th2,CD3~+ 1 ,CD4~+ and CD4~+/CD8~+(P<0.05)in acute stage. Groups of seroconversion patients in recovery stage had a significant decrease of IL-12, IFN-γ, IL-4, Th1/Th2,CD3~+ 1,CD4~+ and CD4~+/CD8~+(P < 0.05). Groups of Anti-HEV IgM no seroconversion, patients had a significant decrease of IL-12,IFN-γ, Th1/Th2,CD3+ 1 ,CD4~+ and CD4~+/CD~8(+)(P <0.05)in recovery stage. There were a significant decrease of Th1/Th2,CD4~+/CD8~+(P <0.05). But there were a significant increased of IL-4 and CD8~+ compared with normal controls(P < 0. 05).CONCLUSION:The increased IL-4 levels may also influence convalescence. The regulating the balance of Th1/Th2 may be a new route of preventing persistent viral infection. It is highly important that the CD4 ~+ T cells and the CD8~+ T cells bear responsibility for viral clearance, but the imbalance of the CD4 ~+/ CD8 ~+probably results in the persistence of HEV infection.