Cordyceps, a caterpillar fungus is found to be used as high medicinal value by the people around the world. It is known as Yartsa Gunbu in Tibeto-Bhutanese, words originating from Tibetan language, meaning Yartsa: grass in summer and Gunbu: worm in winter, it is called “Dong chong Xia cao” in China and “Tockukaso” in Japan, words meaning the same. It grows on high Himalayan plateau, altitude between 3500 to 5000 meters. Well known species of genus Cordyceps is Cordyceps Sinensis (CS) which is being widely used for clinical treatments and researches. Cordyceps Sinensis is a dead remain of Himalayan Ghost moth belonging to a species Hepialis aromoricanus, also called as bat moth. It is considered to have high medicinal value and used to treat diseases like cancer, diabetes, pulmonary diseases, cardiovascular disorder, sexual dysfunction, renal disease and many other diseases for centuries in Chinese Traditional Medicine and Bhutanese Indigenous Medicine. Advanced Biotechnology has revealed that CS has wide range of bioactive constituents and minerals. There are numbers of researches conducted and have seen good impact of this CS on animals, cell cultures and on some cases of human patients, many researches demonstrated its ability in suppressing the tumor cells of various types of cancer. However, few hypotheses contradicted that CS suppresses the immunity. Due to lack of proper trials and studies on human, there is no authenticated or standard protocol that has been formulated for its prescription and clinical use in modern medicine.