In this experiment, indica rice was used as raw material to koji-making, the koji-making conditions of Aspergillus oryzae were optimized and the effects of inoculation temperature, inoculation quantity, culture humidity, culture temperature, and culture time on enzyme activity were studied. The results indicated that the optimum koji-making conditions were as follows: inoculation temperature at 35℃, 0.25% inoculation quantity, culture humidity at 75%, culture temperature at 37℃, 56 h culture time. Under the above conditions, the glucoamylase activity and α-amylase (liquefying enzyme) activity could reach up to 475.52 u/g koji and 177.12 u/g koji respectively. When the culture temperature was 33℃, acidic protease activity reached a maximum of 59.68 u /g.