Our research on juvenile Oncorhynchus masou masou in oyster mushroom supplemented diet was studied to investigate the effect of feeding. Mixing of feed ingredients for dried oyster mushrooms, 3.5, 7.0, 10.5, 14.0 (%) was added to the amount of oyster mushroom dietary beta-glucan content of the more abundant. After the weight of feed given to salmon survey oyster mushrooms diet for 3.5 to 7.0% was similar to the formula feed and the weight of the fish ate oyster mushroom feed over 10.5% were reduced. The oyster mushroom of the experimental diets containing 3.5 to 7.0 percent hepatosomatic index and feed coefficient figure was similar to those of the formulated diets. Therefore we have juvenile cherry salmon fed diets containing 3.5 to 7.0% was considered good to eat and additional research on the immune response will be carried out was necessary.