When thiamine was added to the broth without pyridoxine, Saccharomyces carlsbergensis 4228 was shown to have a retarded growth in the broth containing casamino acids, ammonium sulfate, L-glutamine, L-glutamic acid or L-asparagine as N sources, but when both thiamine and pyridoxine were added to the broth, it showed a complete recovery of the growth. Thiamine-adapted Sacch.carlsbergensis (B_1-1 and B_1-100) and Sacch.cerevisiae Hansen were proved to show similar growth in the broths containing casamino acids or other N sources, either at the presence or at the absence of thiamine in the broths. At the presence of pyridoxine in the broth without thiamine, all the 4 strains of yeasts were able to grow similarly but the growth was slower than that in the broth with both. The utilization of casamino acids, ammonium sulfate and L-asparagine by Sacch. carlsbergensis in the broth with thiamine and pyridoxine was proved to be same, when N content of each was, or less than 0.5mg per tube.