Soy sauce which was prepared with a mixture of cefatted soybeans and wheat flour koji added into acid-hydrolyzed soy sauce was evaluated for the chemical changes in levulinic acid, ethanol and amino acids composition during fermentation, Results showed that the highest reducing sugar content of 12.13∼15.76% was found after 20∼40 days fermentation. The contents of total nitrogen, amino nitrogen, and ethanol increased with increase in fermentation time. A high levulinic acid content was found at the initial fermentation period which was gradually decreased with further fermentation. The content of lactic acid also increased during fermentation. Amino acids such as Glu, Leu, Ala, Phe, Asp, Thr, Ser. Gly, Met, Tyr, Lys, His, Arg and Pro were detected in all tested groups. Higher values were found particularly for Glu, Leu, Ala and Phe and lower values for His, Tyr and Met. The most of amino acids increased in their contents after 120 days of fermentation.