Rhizopogon roseolus (Corda) Th.M.Fr., known as "shoro" in Japanese, is a hypogeous basidiomycete that is an ectomycorrhizal symbiont of Pinus thunbergii.To cultivate shoro mushrooms, we selected superior isolates that rapidly colonized and produced a lot of ectomycorrhizas in the host root and developed a new inoculation by method using mycelial slurries containing a surfactant.