It was found that more than 0.3gι-malic acid, smaller amounts of succinic acid, pyruvate and mucilage, besides mycelia were produced by Schizophyllum commune in 100ml of the cultured medium, initially consisted of 1g etanol, 1g CaCO_3,0.5μg B_1,mineral salts and tap water. The ι-malate production from ethanol and CaCO_3 was observed not only with all strains of S. commune, but also with some unidentified mushroom strains. In some cases, the sum of organic acids estimated as ι-malic acid and mycelia from the medium amounted to more than 1g. It was shown that no ι-malate would be produced from ethanol and CaCO_3 through CO_2-fixing process. (Received Jan. 23,1971)