In order to evaluate the applicability of enzyme electrophoresis for the identification of intra/interspecific hybride obtained by the protoplast fusion in Trichoderma, soluble proteins, intracellular soluble enzymes and extracellular $eta$-glucosidase were analyzed by polyacrylamide gel electrophorsis. As the results, patterns of soluble protein, and isozyme patterns of peroxidase, malate dehydrogenase, and $eta$-glucosidase in hydrids were defferent from those in parental and wild type strains. Therefore, it was established that the analysis of protein pattern by electrophoresis could be applied to isolate and identify the hybrids from the protoplast fusion.