The objective of this study was to develop an efficient production system for cellulase preparation with a high level of xylanolytic enzymes using soluble carbon sources. When xylose and arabinose were simultaneously fed with glucose and cellobiose, a mutant of Trichoderma reesei, M3-1, showed sufficient levels of cellulolytic and xylanolytic activities, indicating that xylose and arabinose are good inducers for the production of xylanolytic enzymes. In a continuous feeding experiment using glucose/cellobiose and glucose/xylose/cellobiose, cellulase preparations with various levels of xylanolytic enzymes were obtained by altering the feeding solutions and the timing of their addition. The volumetric production rates for xylanolytic activities at the glucose/xylose/cellobiose-feeding phase were significantly higher than at the glucose/cellobiose-feeding phase, while those for cellulolytic activities were comparable under the two conditions. Thus the composition of the enzyme preparation produced by the mutant was readily controlled by varying the inducers and the pattern of their addition, facilitating the tailored production of enzymes in a diversity of bioconversion processes.