To investigate the antiviral activity of Xiao'er Baotaikang Granuels on influenza virus in vitro.Methods:We observed the cytotoxic effect of different concentrations of Xiaoer Baotaikang Granules on Madin-Darby canine kidney（MDCK) cells by cell culture technology,used MTT method combined with CPE method to detect cell survival rate and virus inhibition rate,calculated the drug's antiviral index TI,and used ribavirin as positive control drug to evaluate the antiviral activity of the drug against influenza A and B viruses.Results:The 50% cytotoxic concentration (CC50) of Xiaoer Baotaikang Granules on MDCK cells was 5.6 mg/mL,and the 50% effective concentration (EC50) for MDCK cells infected by influenza A H1N1 virus was 2.1 mg/mL,while for influenza B viruses The EC50 was 1.44 mg/mL,and the antiviral indexes were 2.64 and 3.89,respectively.In the positive control drug experiment,when ribavirin was 200 μg/mL,the inhibition rate of influenza A and B viruses reached more than 70%.Conclusion:Xiaoer Baotaikang Granules are a kind of antiviral drugs that have antiviral effects on different types of influenza virus infections.It has clinical application prospects and further research value.