For the effective seedling production of the sweetfish, Plecoglossus altivelis, dietary value of live food in the growth and survival rate of the larvae was examined. To investigate dietary value of three types of rotifers (L-type, S-type, Us-type rotifer) for the sweetfish larvae, the larvae were fed with alone or mixed with each type and with mixtures of two or three types. Although the survival rates of the larvae fed different types of rotifers were not significantly different among them, the larvae fed a mixture of three types of rotifers showed the highest growth significantly. A feeding trial was conducted to determine the effect of the dietary values of rotifer and Artemia nauplius enriched with Chlorella ellipsoidea, $omega-yeast$, spray-dried Spirulina platensis, and Super Selco for the sweetfish larvae. The dietary values of rotifer and Artemia nauplius enriched with Super Selco mixed with spray-dried S. platens is were distinctly improved for the survival rate and growth of the larvae. With regard to effect of the green water with Chlorella ellipsoidea, spray-dried Spirulina platensis, and the addition of photosynthetic bacteria (Rhodopseudomonas capsulatus), the green water with Spirulina platens is mixed with photosynthetic bacteria also enhanced the growth and survival rate of the larvae.