Fermentation tests on sake-mashes were carried out using Kyokai No.10 yeast (K-10, including non-forming type K-1001), together with 6 other Kyokai sake yeasts and 12 other brewer's yeasts. In the analysis of fermentation products, such as aroma compounds and organic acids, the sake brewed by K-10 showed the highest concentration of n-propyl alcohol and the lowest concentration of i-butyl alcohol among them. K-10 is clearly distinguishable from other yeasts by this property. It was found by cluster analysis of analytical data, that K-10 was characteristic among sake yeasts, and that sake yeasts (including K-10 yeast) could be distinctly separated from other brewer's yeasts.