Abstract： Professor ZHENG Qizhong holds that influenza virus is the pathogen of epidemic toxin. Patients with influenza are insufficient in healthy qi and they externally contracted epidemic toxin. After the contraction， patients may have cold syndrome and heat syndrome. Influenza in some children may be caused by the attack of latent pathogen induced by epidemic toxin. The treatment should follow the principle of cold damage and warm disease，distinguish cold and heat，take into account latent pathogen，and give consideration to healthy qi. In clinical practice，Daqinglong Tang，Chaige Jieji Tang，Puji Xiaodu Yin，Ganlu Xiaodu Pellets，Dayuan Yin，Shengjiang Powder and other prescriptions that are commonly used can help achieve good effects.