Equilibrium ratios of minute amounts of ethyl n-caproate, ethyl n-caprate, ethyl n- laurate, beta-phenethyl alcohol and beta-phenethyl acetate in ethanol aqueous solution were measured to obtain the following results. 1. Constant equilibrium ratio was confirmed below the concentration of 10(-2) mole fraction for each minute component in ethanol. 2. It was obvious from the measurements of equilibrium ratios of each minute component in ethanol aqueous solution that equilibrium ratios of each minute component are independent of its concentrations below 800 ppm, and increase with decreasing ethanol concentration in the same manner as the other minute components in Shochu mash.