The invention relates to a Chinese herbal medicine complex enzyme preparation and a method for preparing straw feed by means of the Chinese herbal medicine complex enzyme preparation. The Chinese herbal medicine complex enzyme preparation is prepared by adding and mixing various enzymes, brewer's yeast and Chinese herbal medicine according to the certain proportion. The straw is fermented and degraded by means of complex enzyme and brewer's yeast, the straw is converted into crude protein, amino acid, oligosaccharide and other nutrient substances to be utilized by beasts and birds, and various enzyme systems are utilized for supplementing insufficient endogenous enzymes in digestive tracts of beasts and birds; the straw feed prepared through the Chinese herbal medicine complex enzyme preparation is obviously better than that prepared through natural fermentation, the content of crude fiber is lowered, and the contents of crude protein, crude fat, and crude ash and total sugar are obviously increased; after pigs are fed with the straw feed prepared through the Chinese herbal medicine complex enzyme preparation, the weight of each pig can be increased by 9.52%, the feed conversion ratio is lowered by 9.66%, and the morbidity is lowered.