AbstractThe cellulase production from immobilizedTrichoderma reeseicomposites prepared by radiation polymerization at low temperature was studied. The production of cellulase from the cells irradiated by radiation was slightly retarded at the initial stage of the culture, but was immediately recovered. The production of cellulase resulting from the growth of the immobilized cells proceeds efficiently in the composite having a porous polymer matrix, in which the productivity of cellulase varied with the hydrophilicity, the shape of the composite, monomer, and cell concentration. It was found that cellulase produced by immobilized growing cell composites effectively hydrolyzed cellulosic wastes such as newspaper and chaff which are pretreated by irradiation and crushing.