To improve mycelial growth of Tricholoma matsutake, various physico-chemical characteristics of medium materials and sawdust as the culture substrates were examined. Among the materials tested, soil of pine tree forest, celite and sawdust of Fagus crenata which was pre-treated by hot water extraction for removing inhibitory ingredients of raw sawdust showed good mycelial growth when supplemented the basal nutrient solution to those substrates. However, mycelial growth on the soil and celite was restricted only on the surface of substrates. On hot water treated sawdust the mycelia could grow into substrate, and showed the highest mycelium density among the substrates tested. The sawdust substrate could allow mycelial growth over 80 days although growth on agar medium ceased at around 40 days of cultivation. It is suggested that the sawdust substrate can be applied for the cultivation of mycorhizal mushrooms. The improvement of the composition of nutrient solution supplemented to the sawdust substrate for mycelial growth of Tricholoma was also examined. The optimal pH range of nutrient solution for mycelial growth was between 5 and 6. Glucose and fructose concentrations as a sole carbon source in the nutrient solution were 1% and 1%, respectively. The addition of extract bonito, corn steep liqueur and hot water extract from fruit-bodies of Flammulina and Lentinus mushrooms increased mycelial dry weights of this mushroom.