In addition to DL-lysine (Kawado et al., J. Ferment. Bioeng., 76, 391-394, 1993), DL-2-aminoadipate was found to induce sporulation in a wild-type yeast of Saccharomyces cerevisiae 4011 growing in a nutrition-rich medium without potassium acetate. In the presence of the acid at 10 mM, the sporulation frequency of the yeast cells increased in parallel with the growth and reached maximum (26%) in the stationary phase. Despite the expression of a meiosis inducer gene, IME1, no sporulation was induced unless DL-lysine or DL-2-aminoadipate was included in the nutrition-rich medium. By using DL-2-aminoadipate in combination with glutathione, sporulation was also induced in industrially used sake yeasts growing in the nutrition-rich medium without-potassium acetate.