Due to the high prevalence of viral infections having no specific treatment and the constant appearance of resistant viral strains, the development of novel antiviral agents is essential. The aim of this study was to evaluate the antiviral activity of aqueous and ethanolic extracts of Aegle marmelos against Influenza A (H1N1) pdm09. The extracts were subjected to cytotoxicity as well as antiviral activity on MDCK cells. The concentration range from 10 to 100?g/ml in MDCK cell line was conducted. It showed that the treated cells with drug was nontoxic to the cells at the concentration of 50?g/ml for ethanolic and 60?g /ml for aqueous extract at 48 hrs to 72 hrs and was comparable to that of controls. Hence crude extract of both ethanolic and aqueous up to 50-60?g /ml (CC50) could be used to test the antiviral activity without affecting much of the cell viability. In simultaneous anti-viral assay, 80% viral inhibition was observed at the concentration of 50?g/ml in aqueous extract whereas 100 % viral inhibition was observed in ethanolic extract at concentration of 60?g/ml. In the post treatment assay, the aqueous extract did not show viral inhibition, whereas the ethanolic extract showed 100% reduction at the concentrations of 60?g/ml. This data suggest that ethanolic extract inhibit the Influenza virus infection by blockage of viral attachment by inhibition of viral HA protein, this is consistent with previous studies