Abstract:Objective: To supply the basis of the breeding the host of parasite of Cordyceps sinensis for it‘s natural culturing, by studying the biology of the host of parasite of C. sinensis ,Hepialus biruensis. Method:The host of parasite was collected in field, eclosion, mating and spawning in the different conditions were made,and it‘s biology and the regularity of the growth and development were observed. Result and Conclusion: In the natural condition ,H. biruensis has the rate of eclosion,42.3%,and the sex ratio, 1:0.86,and it‘s lifespan is 2-5 days. It has the rate of eclosion,67.4%,in the constant temperature. At the 18℃,H. biruensis has the highest rate of mating and spawning,92% and 98% ,and its rate of mating and spawning varies in the different temperature conditions. The male moth cherishes average 814. 4 eggs and lays 607. 2 eggs. In the open country, the optimum air relative humidity for mating and laying eggs is 75%-90% ,while indoors, the optimum air relative humidity is 78% .