The effects of extracts from licorice (Glycyrrhisa glabra), great nettle (Urtica dioica), common burdock (Arctium lappa), and bur marigold (Bidens tripartite) on the humoral and cellular immune response and nonspecific resistance in mice were studied. Burdock and bur marigold extracts stimulated the humoral immune response, nettle and licorice extracts stimulated cellular response and nonspecific resistance, their effects being superior to those of pharmacopoeial Echinacea purpurea tincture.