Trichoderma reesei is one kind of filamentous fungi exishng in nature universally. Ithas a long history as an industrially important strain efficiency producing various hydrolases. Themolecular biological progressbe reviewed in the following respectS: thensformahon systems, genecloning; expression and regulation of genes, and produchon of homologous and heterologous proteinsby the T reesei recombinant stains with novel characterishcs, which were modified by geneticengineenng.