Cotton knitted interlock fabric is treated with purified Trichoderma reesei cellulases. The action of cellobiohydrolases I and II (CBH I and CBH II) and endoglucanases I and II (EG I and II), alone and in different combinations, i.e., endo-endo, endo-exo, and exo-exo, is evaluated for reducing sugars, solubilized oligosaccharides, weight loss, bursting strength, and pilling tendency. According to the results, there are clear differences between individual enzymes and their defined mixtures. There is no correlation between high weight loss and good pilling results, and similarly, there is no correlation between weight and strength loss. Thus, the reduced pilling tendency can be obtained with significantly lower strength losses by tailoring the amount and type of different cellulases in the enzyme mixtures.