[Introduction] Matsutake mushroom (Tricholoma matsutake), an ectomycorrhizal fungus has low activity for polysaccharide hydrolyzing enzymes such as amylase, cellulase and hemicellulase. Therefore, only glucose and a few other monoand di-saccharides can be used to grow this fungus. Then, we examined the possibility for the mass production of the mycelia using the saccharified rice bran as growth substrate. [Methods and Results] For the selection of Kouji-mold, 32 strains of Aspergillus spp. were tested. These fungi were cultivated in potato dextrose liquid (PDL) medium added rice bran and amylase activities were assayed. As a result, Kouji-mold from Isesou Mugi Kouji (Asp. oryzae) was selected to use for saccharification of rice bran. When the saccharified rice bran was used as the growth substrate, the mycelical growth was enhanced. In this mushroom, the dry weight mycelia increased at about 3.0 times (control : 50mg, saccharified rice bran : 160mg, 60days, 24℃) by using saccharified rice bran compared with that of the control without saccharified rice bran. From there results, we see that saccharified rice bran is a useful culture material for the mass production of matsutake mycelia. Chemical analysis in saccharified rice bran solution was done with TLC and HPLC. The large amounts of glucose and maltose were detected in the saccharified solution. Now, we are trying to hydrolyze of cellulose and hemicelluloses components in rice bran using Asp. kawachii or Asp. saitoi isolated from Shouchu kouji.