The antiviral activity of aqueous and ethanol extracts from the fruiting bodies of gasteroid Basidiomy-cetes of Western Siberia: Lycoperdon pyriforme, Lycoperdon perlatum, and Phallus impudicus, as well as an aqueous extract from cultivated mycelium of P. impudicus and total polysaccharides from it, on MDCK cell culture against influenza A virus, was studied. Aqueous and ethanol extracts from the fruiting bodies of all studied gasteroid fungi showed antiviral activity against human influenza virus A/Aichi/2/68 (H3N2) and bird A/chicken/Kurgan/05/2005 virus (H5N1). At the same time, extracts from P. impudicus and L. pyriforme showed more pronouncing antiviral activity compared to the activity of the reference drug Tamiflu against the A/H5N1 avian influenza virus. A high antiviral efficacy of an aqueous extract from cultivated mycelium of the P. impudicus and a sample of total polysaccharides from this extract against the A/H5N1 avian influenza virus was revealed.