To examine the influence of a phenolic compound on the production of cellulolytic and xylanolytic enzymes of a woodrotting fungus Coriolus versicolor, a two-dimensional map of enzyme activity was constructed with various concentrations of cellobiose and vanillin. The productions of CMCase, xylanase, ~-glucosidase, and ~-xylosidase increased with higher cellobiose concentration and were markedly enhanced by addition of vanillin. Higher ratio of vanillin/cellobiose activated the production of these enzymes. Only acetyl esterase, which is not actively produced at the ligninolytic stage of C. versicolor, was inhibited by the monolignol vanillin. As the presence of vanillin is considered to approximate conditions of wood decay more closely than its absence, the present result demonstrates that addition of vanillin, a phenolic compound, enhanced the production of cellulolytic and xylanolytic enzymes for wood cell wall degradation.