The invention discloses a special fermented Chinese herbal medicine feed additive for a laying hen. The special fermented Chinese herbal medicine feed additive is prepared by common fermentation of the following raw materials: 50-60 parts of Chinese herbal medicine mixed powder, 15-25 parts of bran, 12-18 parts of corn flour and 8-12 parts of microbial strain, wherein the Chinese herbal medicine mixed powder is prepared from glossy privet fruit powder, licorice powder, pine needle meal and alfalfa meal; the microbial strain is prepared from lactic acid bacteria, bacillus subtilis and bacillus licheniformis. The preparation method comprises the following steps: 1 respectively drying the taken glossy privet fruit, licorice, pine needle and alfalfa, crushing, screening and mixing evenly to prepare the Chinese herbal medicine mixed powder; and 2 adding the bran, the corn meal and the microbial strain to the Chinese herbal medicine mixed powder, adding purified water, mixing evenly, fermenting to obtain fermented materials, drying the fermented materials, crushing and screening to finish preparation. The additive disclosed by the invention is capable of effectively improving the organism immunity of the laying hen, so that the egg-laying property of the laying hen is improved; and the quality of the laid eggs is improved.