In this study, Cordyceps militaris strain CM3 stored in the collection of Research and Development Center for High Technology Agriculture was used. 9 media for C. militaris cultivation were investigated, and the optimal cultivation medium was found as M9 which consisted of the following components: brown rice 60 g, silkworm pupae 10 g, CaCl₂ 0.1 g/l, folic acid 5 ^g/l, distilled water 90 ml; this medium is suitable for stroma production of C. militaris. Fresh weight, dry weight, and the number of stroma reached 19.54 g/bottle, 3.8404 g/bottle, 70.3 stroma/bottle, respectively. Biologically active substance contents of Cordyceps militaris stroma are adenosine (2.0027 mg/g), cordycepin (7.7551 mg/g), polysaccharide (166.20 mg/g), ergosterol (1.7369 mg/g).