Abstract: The influences of cellulase on structure and related property of the cotton fabric were studied.The micrographs showed that there were corroded phenomena not only on the surface but also into gap and capillary of cotton fiber.The crystallinity of cotton was decreased and partial crystalline could be transfered into amorphous. The polymerization degree of cotton fiber was decreased with the increasing of lost weight rate.Although the fabric qualities such as softness and surface smoothness were improved,the lost weight rate should be controlled about 4%,and the loss of strengh should be also controlled within 10%.The property of fabric would be damaged if the process was not controlled properly.