Cordyceps sinensis is also called the "caterpillar fungus." In the wild it grows on and acquires nutrients from several species of caterpillars. In China, it is referred to as "winter worm, summer grass." This fungus is found at high altitude in the mountains of China, Nepal, and Tibet.

In traditional Chinese medicine,cordyceps sinensis is considered to benefit the lung and kidney channels. It is commonly used by the elder in China as a type of "super-ginseng" for rejuvenation and stamina.

Because it is difficult to collect enough cordycepin from the wild, commercial cultivation methods have been developed by using "submerged culture," where the mycelium is grown in a liquid medium. All scientific research published in the last twenty years is based on hot water extracts of the Cordyceps mycelium cultivated in this manner.