PURPOSE:To obtain the title culture medium useful for mushroom culture, having excellent productivity by sterilizing a waste treatment material or deactivating an enzyme therein by using an extruder for a raw material containing the waste treatment material to give a sterile culture medium, and packing the sterile culture medium into an aseptic chamber. CONSTITUTION:For example, a raw material containing a waste treatment material such as sawdust or rice bran is passed through an extruder (preferably 140-160 deg.C barrel temperature and 20-60kgf/cm<2> inner pressure), and sterilization of the waste treatment material or deactivation of enzyme therein is continuously carried out to give a sterile culture medium and the sterile culture medium is packed preferably at 60-100 deg.C into a device having a delivery part at the side of an aseptic chamber sterilely connected to the die part.
