Abstract: Two dimensional electrophoresis was used to investigate the expression levels of extracellular cellulolytic enzymes of Trichoderma reesei on different carbon sources. The results showed that very low expression levels of CBHⅡ, AxeI and BXL were detected when glucose or glycerol was employed as carbon source. Moderate expression of CBHⅠ, CBHⅡ, EGⅠ, EGⅢ, BXL, AxeI and AglⅠ was observed when cellobiose was used as carbon source. Cellulose induced abundant expression of CBHⅠ，CBHⅡ，EGⅠ，EGⅡ, EGⅢ, EGIV, ManI, ManII, AxeI, BXL and AglⅠ, which accounted for 61％of the secretome. There was some consistency in cellulase composition between the map of cellulose and cellobiose condition, but higher expression levels and enzyme activities were observed when it was induced by cellulose.