PROBLEM TO BE SOLVED: To obtain a spawn for mushroom cultivation, which does not use a broadleaf tree as a raw material, facilitates inoculation operation and has high safety to the human body and to provide a method for producing the spawn for mushroom cultivation and an inoculation method using the spawn. SOLUTION: The sol-like spawn for mushroom cultivation is produced by adding 0.2-1.5 wt.% of a thickener to a liquid medium, sterilizing the medium at a high temperature under high pressure, cooling the liquid medium to a room temperature, inoculating a mushroom mycelium obtained by culture from a strain for preservation to the liquid medium and culturing the mycelium. The method for inoculating the sol-like spawn comprises using a long lumber or a short lumber as a log for mushroom. COPYRIGHT: (C)2006,JPO&NCIPI