[Objective] The aim was to study the influence of Hypericum perforatum extract(HPE) on IFN-γ,TNF-α of mice infected with influenza A virus(IAV).[Method] HPE(100 mg/kg and 50 mg/kg) and ribavirin(10 mg/kg) were administrated respectively by oral gavage to mice infected with IAV,0.2 ml every times,twice daily,after 5 d,mice were killed.The lung tissues were produced into homogenate and enzyme-labeled immunosorbent assay(ELISA) was used to determine the content of IFN-γ,TNF-α in order to observe whether HPE af...