Objective: To evaluate the anti-influenza virus( H_3N_2) activity in vitro of Bletilla striata extracts,and to study the mechanisms. Methods: The viral hemagglutination titer and nucleic acid amount were used as measurement indicators to evaluate anti-influenza virus activity in embryonated chicken eggs from aqueous extracts and alcohol extracts of the Bletilla striata. The cytopathic effect( CPE) and the hemagglutination inhibition( HI) assay was used to investigate the inhibitory effects and the targets o...