The invention provides a Chinese herbal medicine active fermentation health care liquid for preventing and treating bird flu and a preparation method of the liquid. The invention provides a method that the Chinese herbal medicine fermented by beneficial bacteriums serves as feed supplements to prevent bird flu. The Chinese herbal medicine comprises the following herbals: cyrtomium fortunei, radix isatidis, membranous milkvetch root, Chinese thorowax, fructus forsythiae, coptis chinensis, honeysuckle, baical skullcap root, liquorice, folium mori, chrysanthemum morifolium ramat, platycodon root, burdock, bamboo leaf, rhizoma phragmitis, mentha haplocalyx, almond and folium eriobotryae. The Chinese herbal medicine is smashed, soaked, decocted, and fermented by the beneficial bacteriums to produce a Chinese herbal medicine active fermentation health care liquid for preventing and treating bird flu, wherein the beneficial bacteriums used during the fermentation process are mainly saccharomycete, lactic acid bacteria, photosynthetic bacteria, bifidobacterium, bacillus and the like. The Chinese herbal medicine active fermentation health care liquid has the effects of preventing and treating bird flu, promoting growth and improving chicken intestinal flora, and has the advantage that the application is easy, the dosage of Chinese herbal medicine is small, the amount of live bacterium of large and the drug residues and the resistance to drug is avoided.