The invention discloses food waste deodorization composite bacteria and a preparation method thereof, and the preparation method comprises the following steps: respectively performing high-density culture on strains of trichoderma viride, bacillus subtilis, bread mold, photosynthetic bacteria, saccharomyces cerevisiae, bacillus licheniformis, nitrosomonas europaea and nitrobacterwinogradskyi, performing dehydration and drying on various types of monoxenie obtained by high-density culture to prepare hypopus microbial dry powder, and then mixing according to the weight ratio of 10-20 parts of the trichoderma viride, 10-15 parts of the bacillus subtilis, 20-30 parts of the bread mold, 5-10 parts of the photosynthetic bacteria, 10-20 parts of the saccharomyces cerevisiae, 10-15 parts of the bacillus licheniformis, 5-15 parts of the nitrosomonas europaea and the 5-15 parts of the nitrobacterwinogradskyi to prepare the food waste deodorization composite bacteria. The food waste deodorization composite bacteria are used for deodorization of waste; and compared with the prior art, the method has the advantages that the production investment is low, the production cost is low, the use is convenient and the deodorization effect is good.