The invention relates to the technical field of microorganism fermentation engineering and aims to provide an application of Trichderma asperellum in the fermentation method for converting and utilizing traditional Chinese medicine residues. Cellulase, beta-glucanase, xylanase, pectinase and other enzyme series, generated by Trichderma asperellum are used to decompose the components of the cell walls of the traditional Chinese medicine residues, such as cellulose, hemicellulose and pectic substances and convert the components to micromolecular sugar, monosaccharide, polypeptide, amino acid and the like which can be directly used by animals, thus increasing the nutrient content; and the cell walls are broken down so that the effective ingredients and nutrients of the traditional Chinese medicine residues can be fully dissolved. Finally a green feed additive with both medicinal function and nutritional function can be prepared and the problems of the pollution of the traditional Chinesemedicine residues and the shortage of the traditional Chinese medicinal feed additive can be solved.