The Cordyceps genus includes many species of fungi, most of which are endoparasitoids on arthropods.The distribution of these fungi is cosmopolitan, but many occur in regions such as Asia with a hot, humid climate. These pathogens of insect pests are promising candidates for use as biological control factors. Entomopathogenic fungi including the famous Cordyceps sinensis produce bioactive compounds. Lately Cordyceps sinensis was renamed Ophiocordyceps sinensis. This fungus has a long history as a medicinal fungus. It germinates in a living host, kills and mummifies the larva, and then grows from the body of the host. Is known in Tibet as the “winter worm, summer grass”,or “Caterpillar fungus” (Yartsa gunbu). Collecting Ophiocordyceps has become an important source of money for local households in Nepal. Ophiocordyceps sinensis is cultivated as an anamorph for its medicinal and pharmaceutical properties in an artificial medium on an industrial scale. Ophiocordyceps compounds have immunostimulating properties and antitumor activity.