This study was carried out to explore for the possibility of recycling the pine wood sawdusts for the substrate for enokitake (Flammulina velutipes) cultivation. The wood species of sawdusts cultivated for enokitake mushroom were identified mostly as hard pine (Pinus spp.). Distribution of enokitake hyphae was restricted to ray parenchymas and tracheids exposed to fungi. Nevertheless, degree of cell wall degradation by enokitake was slight. Light microscopic observation showed the thinning of secondary cell wall in some tracheids. Under polarized microscopy the 1()ss of birefringence was observed only in a few latewood tracheids. All the middle lamella remained intact. The present work showed clearly that pine sawdusts used as substrate for enokitake cultivation held enough cell wall materials for mushroom cultivation. The relative resistance of softwood cell walls against enokitake fungus was also discussed.